General terms|ETG                     |An early-type galaxy, collectively referring to a galaxy in the range of types E-Sa
General terms|ITG                     |An intermediate-type galaxy, taken to be in the range Sab-Sbc
General terms|LTG                     |A late-type galaxy, collectively referring to a galaxy in the range of types Sc-Im
General terms|ETS                     |An early-type spiral, taken to be in the range S0/a-Sa
General terms|ITS                     |An intermediate-type spiral, taken to be in the range Sab-Sbc
General terms|LTS                     |A late-type spiral, taken to be in the range Sc-Scd
General terms|XLTS                    |An extreme late-type spiral, taken to be in the range Sd-Sm
General terms|Classical bulge         |A galaxy bulge that likely formed from early mergers of smaller galaxies (Kormendy & Kennicutt 2004ARA&A..42..603K; Athanassoula 2005MNRAS.358.1477A)
General terms|Pseudobulge             |A galaxy bulge made of disk material that has secularly collected into the central regions of a barred galaxy (Kormendy J. 2012; Secular Evolution of Galaxies, XXIII Canary Islands Winter School of Astrophysics, ed J. Falcon-Barroso and J. H. Knapen (Cambridge: Cambridge Univ. Press) 1)
General terms|PDG                     |A pure disk galaxy, a galaxy lacking a classical bulge and often also lacking a pseudobulge
Stage        |Stage                   |The characteristic of galaxy morphology that recognizes development of structure, the widespread distribution of star formation, and the relative importance of a bulge component along a sequence that correlates well with basic characteristics such as integrated color, average surface brightness, and HI mass-to-blue luminosity ratio
Elliptical   |E galaxy                |A galaxy having a smoothly declining brightness distribution with little or no evidence of a disk component and no inflections (such as lenses) in the luminosity distribution (examples: NGC 1052, 3193, 4472)
Elliptical   |En                      |An elliptical galaxy of visual flattening n=10(1b/a), where b/a is the visual isophotal axis ratio (Hubble 1926ApJ....64..321H)
Elliptical   |E^+^n                   |A "late" elliptical of visual flattening n, a transition stage to the S0 class (de Vaucouleurs 1959HDP....53..275D); show slight traces of differentiated structure, usually subtle evidence of lenses (example: NGC 5846) or a faint outer envelope; also has been used as a "home" for Morgan cD galaxies in RC3
Elliptical   |E/E^+^                  |An E galaxy that in our Phase 1, 2 analysis averages between E and E^+^ (example: NGC 3226)
Elliptical   |E(d)n                   |A disky elliptical galaxy of visual flattening n (Kormendy & Bender 1996ApJ...464L.119K); a subclassification of ellipticals having pointy outer isophotes that is visually detectable only for the most obvious or most favorably oriented cases (example: NGC 3377)
Elliptical   |E(b)n                   |A boxy elliptical galaxy of visual flattening n (Kormendy & Bender 1996ApJ...464L.119K); a subclassification of ellipticals having boxy outer isophotes that is visually detectable only for the most obvious cases
Elliptical   |E(b,nd)                 |A boxy E galaxy with an inner disk (example: NGC 4370)
S0 gal.      |S0 galaxy               |A disk-shaped galaxy lacking strong or obvious spiral structure; at minimum, a two-component system with a bulge and a disk
S0 gal.      |S0^-^->S0^o^->S0^+^     |a stage sequence of S0 galaxies based on increasing development of structure, such as bars, lenses, and rings
S0 gal.      |E^+^/S0^-^              |An ETG that in our Phase 1, 2 analysis averages between E^+^ and S0^-^ (example: NGC 4649)
S0 gal.      |S0^-^                   |An early S0 showing clear evidence for a disk (envelope) but little structure; all features are subtle (examples: NGC 4442, 5507)
S0 gal.      |S0^-/o^                 |An S0 galaxy that in our Phase 1, 2 analysis averages between S0^-^ and S0^o^
S0 gal.      |S0^o^                   |An intermediate stage S0 showing clear lenses or traces of rings/pseudorings (examples: NGC 1411, 1533)
S0 gal.      |S0^o^[d]                |One example of a notation used for an apparently early-type galaxy in the catalog having little or no apparent bulge; other examples include [c], [cd], [m]. These are related to the van den Bergh (1976) parallel-sequence Hubble classification system, although that system is not fully built into the catalog (example: NGC 693)
S0 gal.      |S0^o/+^                 |An S0 galaxy that in our Phase 1, 2 analysis averages between S0^o^ and S0^+^
S0 gal.      |S0^+^                   |A late S0 stage showing strong rings and bars, and in some cases trace spiral structure (examples: NGC 1291, 1326, 4138)
S0 gal.      |S0^+^[c]                |A late S0 with an Sc-like central concentration (examples: NGC 4344, 4451)
Spiral & Irr.|Spiral galaxy           |A galaxy where a spiral pattern is a major part of the morphology
Spiral & Irr.|S0/a-Sa-Sb-Sc-Sd-Sm     |A stage sequence for spirals (with intermediate types Sab, Sbc, Scd, and Sdm) based on Hubble's three criteria: relative prominence of the bulge, the degree of openness of the arms, and the degree of resolution of the arms into star clusters or very luminous stars
Spiral & Irr.|Irregular galaxy        |A complex system characterized by an irregular distribution of star formation; this irregular distribution can, however, be embedded in a more regular background
Spiral & Irr.|S\underline{0}/a        |An S0/a galaxy that is closer to S0^+^ than to Sa (examples: NGC 522, 2681, 3626)
Spiral & Irr.|S0/a                    |A transition stage showing clear but subtle tightly wrapped spiral arms; structure is generally smooth but trace star formation is seen in nearby examples (examples: NGC 1350, 1452, 4394, 4454, 4984, 5701, 6340, 7098)
Spiral & Irr.|S0/\underline{a}        |An S0/a galaxy that is closer to Sa than to S0^+^ (examples: NGC 3185, 3900)
Spiral & Irr.|Sa                      |An early-type spiral, usually defined by relatively smooth, tightly wrapped spiral arms and a significant bulge; standard interpretation may be violated in a cluster environment or in presence of a bar (examples: NGC 1433, 1512, 3031, 3788, 4260, 4450, 4548, 4800, 7513)
Spiral & Irr.|S\underline{a}b         |An Sab galaxy that is closer to Sa than to Sb (example: NGC 2985)
Spiral & Irr.|Sab                     |An intermediate-type spiral galaxy similar to Sa but with a more knotty structure (examples: NGC 210, 1097, 3992, 4995; IC 1993)
Spiral & Irr.|Sa\underline{b}         |An Sab galaxy that is closer to Sb than to Sa (examples: NGC 3177, 4902)
Spiral & Irr.|Sb                      |An intermediate-type spiral having relatively more open, knotty arms and a smaller bulge than Sa or Sab galaxies (examples: NGC 908, 3433, 3689, 3705, 4237, 7479)
Spiral & Irr.|S\underline{b}c         |An Sbc galaxy that is closer to Sb than to Sc (examples: NGC 3344, 3512; IC 769)
Spiral & Irr.|Sbc                     |Typically, an intermediate-type galaxy having well-developed, open, knotty spiral arms like an Sc galaxy but with a more significant bulge (examples: NGC 1365, 3184, 3198, 3338, 3726)
Spiral & Irr.|Sb\underline{c}         |An Sbc galaxy that is closer to Sc than to Sb (examples: NGC 2715, 4303)
Spiral & Irr.|Sc                      |A late-type spiral having well-developed, open, and knotty spiral arms with a small but significant bulge (examples: NGC 1042, 1084, 3486, 3810, 3893, 4411 B, 5457, 5970, 7448; IC 1953)
Spiral & Irr.|S\underline{c}d         |An Scd galaxy that is closer to Sc than to Sd (examples: NGC 1073, 5033, 5468)
Spiral & Irr.|Scd                     |Similar to an Sc but with little or no bulge; typically a small central object (nuclear star cluster or pseudobulge) may be seen; arms can be more open than for an Sc; these are generally pure disk galaxies (PDGs; examples: NGC 1255, 1559, 3346, 5334, 5595, 7741)
Spiral & Irr.|Sc\underline{d}         |An Scd galaxy that is closer to Sd than to Sc (examples: NGC 255, 1253, 3359, 4411 A, 5597, 5668)
Spiral & Irr.|Sd                      |An extreme late-type spiral, similar to Scd but with less apparent central concentration than an Scd; among the most common PDGs; asymmetry is often present but less extreme than in Sdm or Sm,Im types (examples: NGC 3003, 4294, 4731, 5068, 5669)
Spiral & Irr.|S\underline{d}m         |An Sdm galaxy that is closer to Sd than to Sm (examples: NGC 247, 3556, 7151, 7497)
Spiral & Irr.|Sdm                     |An extreme late-type spiral showing considerable asymmetry, usually with one arm longer and better defined than the other; considerable star formation also characterizes these PDGs (examples: NGC 300, 3906, 4395, 4630, 7154)
Spiral & Irr.|Sd\underline{m}         |An Sdm galaxy that is closer to Sm than to Sd (example: NGC 2552)
Spiral & Irr.|Sm                      |A magellanic spiral, usually characterized by a single spiral arm emerging from a bar or central region and little or no bulge or central concentration (de Vaucouleurs & Freeman 1972VA.....14..163D; examples: NGC 55, 5474, 7091)
Spiral & Irr.|S/Im                    |A magellanic galaxy that is closer to Im than to Sm (example: NGC 4353)
Spiral & Irr.|Im                      |A magellanic irregular galaxy, characterized by an irregular shape sometimes within a smooth background of starlight; often show considerable star formation and a wide range of luminosities (examples: NGC 4214, 4242, 4449, 4605)
Spiral & Irr.|Im (cc)                 |A clump cluster, usually referring to an irregular galaxy with a large number of scattered star forming regions. The term was originally applied to high redshift clumpy galaxies (e.g., Elmegreen et al. 2009ApJ...701..306E; examples: IC 1826, 2040; UGC 1945)
Spiral & Irr.|I0                      |A type of galaxy seen mainly in blue light images where a highly irregular dust distribution is seen within an S0 or E-like background; at 3.6 mum, I0 galaxies are relatively normal-looking ETGs (examples: NGC 2968, 3077, 5195, 5253, 5363)
dw. and Sph. |dE                      |A "dwarf elliptical" galaxy, defined to have a "smooth intensity distribution over the face and ... low surface brightness" (Sandage & Binggeli 1984AJ.....89..919S; Non-Virgo example in S^4^G catalog: NGC 59)
dw. and Sph. |dS0                     |A "dwarf S0" galaxy, a class of dwarfs which resemble dE galaxies except for "a change of slope in the radial gradient of the light distribution" showing "either direct evidence of a disk, or ... evidence of two components" (Sandage & Binggeli 1984AJ.....89..919S)
dw. and Sph. |dE, N                   |A nucleated dwarf E galaxy (Sandage & Binggeli 1984AJ.....89..919S)
dw. and Sph. |dS0, N                  |A nucleated dwarf S0 galaxy (Sandage & Binggeli 1984AJ.....89..919S)
dw. and Sph. |dIm                     |A dwarf irregular galaxy, typically an Im galaxy having an absolute B-band magnitude M_B_^0^>~-17; low surface brightness and often resolved in S^4^G images
dw. and Sph. |Sph                     |A "spheroidal" galaxy, a type of galaxy having the appearance of an E or S0 galaxy, but the photometric characteristics of much later-type, lower luminosity galaxies (like Sm, Im types); the dE and dS0 galaxies in the Virgo Cluster are all of this basic type (Kormendy & Bender 2012ApJS..198....2K)
dw. and Sph. |Sph, N                  |A nucleated spheroidal galaxy (Binggeli et al. 1985AJ.....90.1681B; Kormendy et al. 2009ApJS..182..216K)
dw. and Sph. |BCD                     |A star-forming, blue compact dwarf galaxy; at 3.6 mum, can appear as a dE or dS0 galaxy (example: NGC 1705)
Family       |Family                  |The characteristic of galaxy morphology that recognizes the apparent strength of a bar or other type of nonaxisymmetric structure, such as an oval
Family       |SA                      |A nonbarred spiral or S0 galaxy (examples: NGC 488, 628, 1411, 4698; IC 1993, 5267)
Family       |S\underline{A}B         |A galaxy showing a trace of a bar, usually in the form of a broad oval or a very low contrast regular bar (examples: NGC 4203, 4899)
Family       |SAB                     |A barred galaxy of intermediate apparent bar strength (examples: NGC 4535, 5236, 7743)
Family       |SA\underline{B}         |A bar that is clear and well-defined but weaker-looking than a typical SB galaxy bar (examples: NGC 4639, 4818, 5566, 5701)
Family       |SB                      |A barred galaxy with a conspicuous bar, usually strong and obvious (examples: NGC 1300, 1365, 1452, 7513)
Family       |SAB_a_, SB_a_           |A barred galaxy where the bar is defined by brightness enhancements ("ansae"; Sandage 1961hag..book.....S; Danby 1965AJ.....70..501D) at its ends; these enhancements may be round spots, short linear features, arcs, or star-forming clumps (Buta 2013pss6.book....1B; examples: NGC 2787, 5375, 7098 see Figures 12 and 13 for others)
Family       |SAB_x_, SB_x_           |A galaxy showing a prominent X or box/peanut structure in its inner regions; often seen in edge-on galaxies, the box/peanut/X shape is believed to be a manifestation of vertical resonant orbits in a bar potential, thus it indicates the presence of a bar (Athanassoula 2005MNRAS.358.1477A). An X may also be seen in the clear bars of non-edge galaxies (Buta et al. 2007dvag.book.....B; Erwin & Debattista 2013MNRAS.431.3060E; examples: NGC 2654 Figure 14; nearly edge-on; NGC 5377 intermediate inclination)
Family       |SAB_xa_, SB_xa_         |A galaxy showing both an X and a pair of ansae; the X is usually three-dimensional while the ansae are flat. (example: NGC 4216 Figures 12 and 13)
Std in. var  |Inner variety           |The characteristic of galaxy morphology that recognizes the presence or absence of an inner ring
Std in. var  |(r)                     |An inner ring, a closed circular or oval feature enveloping either the ends of a bar if present or the central bulge (examples: NGC 1433, 3351, 3486, 4245, 5566)
Std in. var  |(\underline{r}s)        |A well-defined inner ring, but made of tightly wrapped spiral structure (examples: NGC 613, 1398, 3368, 3705)
Std in. var  |(rs)                    |An inner "pseudoring," a partial inner ring made of spiral arms (examples: NGC 779, 1232, 3346, 4548)
Std in. var  |(r\underline{s})        |A weak inner pseudoring, usually fairly open and characterized by a pitch angle only a little different from that of the outer spiral arms (examples: NGC 1365, 3513, 4501, 4548, 5383)
Std in. var  |(s)                     |A pure s-shaped spiral where the arms break from the ends of a bar or from the bulge without forming a pseudoring (examples: NGC 1300, 7721)
Spe in. var  |(rr)                    |A galaxy having two inner rings (example: NGC 4698)
Spe in. var  |(x_1_r)                 |A ring-like feature that outlines a bar, possibly related to the x_1 family of bar orbits discussed by Regan & Teuben (2004ApJ...600..595R; example: NGC 6012)
Spe in. var  |(r,s)                   |A variety where the inside of an inner ring includes a spiral pattern unrelated to the main outer spiral arms; prototype in this catalog is NGC 5364
Spe in. var  |(rs,rs)                 |A galaxy having two inner pseudorings, usually of very different sizes (examples: NGC 289, 4689)
Spe in. var  |(s,rs)                  |A galaxy having a strong s-shaped spiral in the presence of an inner pseudoring (example: NGC 986)
Spe in. var  |(l)                     |An inner lens, a type of feature, often seen in S0 galaxies, having a shallow brightness gradient interior to a sharp edge (Kormendy 1979ApJ...227..714K; examples: NGC 1291, 1411, 4269, 5602)
Spe in. var  |(rl)                    |An inner ring-lens, recognized as a low contrast inner ring; types (\underline{r}l) and (r\underline{l}) recognize different degrees of contrast enhancement (examples: NGC 2859, 4250)
Spe in. var  |(rs,rl)                 |A galaxy having an inner pseudoring and an inner ring-lens, the latter the smaller (example: NGC 5055)
Spe in. var  |(r'l)                   |An inner pseudoring-lens, where the inner ring shows azimuthal contrast differences like spiral arms (examples: NGC 210, 1415, 3147)
Spe in. var  |(ls)                    |An inner lens with a subtle embedded spiral pattern (example: NGC 3675)
Spe in. var  |(p)                     |A "plume," usually seen as a secondary spiral arc positioned just off the leading sides of a bright inner ring (Buta 1984PASAu...5..472B); much rarer than inner rings or lenses (example: NGC 1433)
Spe in. var  |(bl)                    |A "barlens," a feature recognized by Laurikainen et al. (2011MNRAS.418.1452L, 2013MNRAS.430.3489L, 2014MNRAS.444L..80L) and Athanassoula et al. (2014arXiv1405.6726A) as the inner part of an early-type bar [examples: NGC 1433, 2787, 3351 (see Figure 11)]
Nuc. var     |Nuclear variety         |The nuclear variety classification refers to rings, lenses, bars, and other features that are often found in the centers of barred galaxies, but which may also be found in nonbarred galaxies
Nuc. var     |(nr)                    |A nuclear (or circumnuclear) ring, a small star-forming feature found in the centers of barred galaxies but also sometimes seen in nonbarred galaxies (example: NGC 1097; see Figure 20 for others)
Nuc. var     |(nr')                   |A nuclear pseudoring, where the ring appears formed by a wrapped spiral pattern; in optical images, this character may sometimes be an artifact of inner dust lanes in bars (examples: NGC 1068, 1090)
Nuc. var     |(ns)                    |A nuclear spiral, a type of feature that may also be an artifact of dust in optical bands (example: NGC 1022)
Nuc. var     |(nl)                    |A nuclear lens; an excellent example in the S^4^G catalog is NGC 4250
Nuc. var     |(nrl)                   |A nuclear ring-lens (examples: NGC 210, 1300, 1433, 5566)
Nuc. var     |(nb)                    |A nuclear (or secondary) bar, a feature found in the centers of barred galaxies but which may also be found in SA galaxies (examples: NGC 1291, 1433, 4725)
Nuc. var     |(nb_a_)                 |A nuclear ansae-type bar
Nuc. var     |(nd)                    |A nuclear disk, usually seen in well-resolved edge-on disk galaxies (examples: NGC 24, 678, 1532, 3079, 3628, 4111, 5907)
Nuc. var     |(np)                    |a "nuclear pattern," a nuclear structure of uncertain nature
Nuc. var     |(tb)                    |a triaxial bulge, an elongated central component whose major axis is misaligned with the galaxy major axis
Nuc. var     |(psb)                   |a pseudobulge, an elongated bulge component whose major axis is approximately aligned with the disk major axis (example: NGC 4536)
Combined var |(r,nr)                  |A galaxy having both an inner ring and a much smaller nuclear ring (examples: NGC 1326, 1512, 3351, 4274, 5850)
Combined var |(l,nl)                  |A galaxy having both an inner lens and a nuclear lens (example: NGC 1411)
Combined var |(rs,nr,nb)              |A galaxy having an inner pseudoring, a nuclear ring, and a nuclear bar (example: NGC 4321)
Combined var |(r\underline{l},bl,nr)  |A galaxy having an inner ring-lens (more lens than ring), a barlens, and a nuclear ring (example: NGC 4314)
Std out. var |Outer variety           |The characteristic of galaxy morphology which recognizes a large ring or ring-like pattern in the outer regions of a galaxy
Std out. var |(R)                     |An outer ring, a closed ring-shaped feature usually about twice the size of a bar in barred galaxies (examples: NGC 1291, 1350, 2859)
Std out. var |(R')                    |An outer "pseudoring," a near-outer ring made of spiral arms (examples: NGC 986, 1300, 1365, 5757, 7479)
Spe out. var |(RR)                    |A galaxy having two outer rings, usually of very different sizes (examples: NGC 3898, 4457)
Spe out. var |(R'R')                  |A galaxy having two outer pseudorings, usually of very different sizes (examples: NGC 1425; UGC 8155; PGC 53093)
Spe out. var |(R',R)                  |A galaxy with an outer pseudoring and an outer ring, the latter being the smaller (example: NGC 4984)
Spe out. var |(L)                     |An outer lens, a type of feature, often seen in early-type galaxies, that is an outer analog of an inner lens (Kormendy 1979ApJ...227..714K; examples: NGC 2787, 4262)
Spe out. var |(RL)                    |An outer ring-lens, recognized as a low contrast outer ring; types (\underline{R}L) and (R\underline{L}) recognize different degrees of contrast enhancement (examples: NGC 5602, 5750)
Spe out. var |(RL,R)                  |A galaxy with an outer ring-lens and an outer ring, the latter being the smaller (example: NGC 3626)
Spe out. var |(RL,R')                 |A galaxy with an outer ring-lens and an outer pseudoring, the latter being the smaller (examples: NGC 1367, 4351, 4826)
Spe out. var |(R'L)                   |An outer pseudoring-lens, where the outer ring shows azimuthal contrast differences like spiral arms (examples: NGC 1357, 2780)
OLR morph.   |(R_1_)                  |A closed outer ring showing a shape resembling a broad figure 8; a subtly dimpled oval ring, recognized as an OLR subclass (Buta & Crocker 1991AJ....102.1715B; Buta 1995ApJS...96...39B; examples: NGC 1326, 4250, 5728; IC 1438, 4214)
OLR morph.   |(R_1_L)                 |An R_1_ outer ring-lens (examples: NGC 2893, 5448)
OLR morph.   |(R_1_')                 |An outer pseudoring made from arms that wind about 180deg with respect to the bar ends; an OLR subclass (Buta & Crocker 1991AJ....102.1715B; Buta 1995ApJS...96...39B; examples: NGC 1566, 3504, 4192, 4314, 5377, 7051)
OLR morph.   |(R_2_')                 |An outer pseudoring made from arms that wind about 270deg with respect to the bar ends; an OLR subclass (Buta & Crocker 1991AJ....102.1715B; Buta 1995ApJS...96...39B; examples: NGC 2633, 7741, ESO 26-1)
OLR morph.   |(R_1_'L)                |An (R_1_') outer pseudoring-lens (example: NGC 4045)
OLR morph.   |(R_2_'L)                |An (R_2_') outer pseudoring-lens (example: NGC 210)
OLR morph.   |(R_1_R_2_')             |A combined outer ring-pseudoring pattern where the arms forming the R_2' ring break from an R_1 ring; an OLR subclass (Buta & Crocker 1991AJ....102.1715B; Buta 1995ApJS...96...39B; example: NGC 5101)
OLR morph.   |(R_12_')                |An unusual version of (R_1_R_2_') where only half of each feature is seen.
CR           |Cataclysmic ring        |A ring-like feature formed in a catastrophic galaxy interaction event, such as a head-on collision or major disruption
CR           |Extraplanar disk        |A general term for any acquired disk-shaped feature inclined at an angle to a more massive disk system
CR           |RG                      |A ring galaxy, a term referring to the unusual rings thought to be produced in special galactic collisions (Theys & Spiegel 1976ApJ...208..650T; Madore et al. 2009ApJS..181..572M)
CR           |PRG                     |A polar ring galaxy or related type of object (Whitmore et al. 1990AJ....100.1489W). In the strictest sense, an interacting system where a companion is disrupted along a polar or near polar orbit around another disk-shaped system (example: NGC 5122)
CR           |IRG                     |An inclined ring galaxy, where a companion has been disrupted into a high angle but not necessarily polar orbit (example: NGC 660)
CR           |(R)E                    |A likely accretion ring formed from a companion disrupted into a large orbit around an elliptical galaxy (Schweizer et al. 1987ApJ...320..454S)
Edge-on gal. |sp                      |A "spindle," or highly inclined (generally i > 65deg) disk-shaped galaxy
Edge-on gal. |Scd sp                  |A highly inclined Scd galaxy, too close to edge-on for the family or variety to be reliably distinguished (example: NGC 100)
Edge-on gal. |SB(\underline{r}s)bc sp |A highly inclined galaxy, but sufficiently far from edge-on that the family and variety are distinguishable (example: NGC 253)
Edge-on gal. |spw                     |A highly inclined disk-shaped galaxy where the disk shows evidence of warping in the nearly edge-on view  (examples: NGC 522, 5084, 5403; UGC 10043 Figure 18)
Edge-on gal. |S0^-^ sp/E(d)7          |An edge-on early S0 galaxy, having a disky thick disk of flattening E7 (example: NGC 1032); E(d) is Kormendy & Bender (1996ApJ...464L.119K) notation and is used here only in a descriptive manner
Edge-on gal. |S0^-^ sp/E(b)6          |An edge-on early S0 galaxy, having a boxy thick disk of flattening E6 (example: NGC 1332); E(b) is Kormendy & Bender (1996ApJ...464L.119K) notation and is used here only in a descriptive manner
Edge-on gal. |S0^-^ sp/E5-6           |An edge-on early S0 galaxy, having an E-like thick disk (neither boxy nor disky) of flattening E5-6 (example: NGC 3115)
Edge-on gal. |Sb sp/E5                |An edge-on Sb galaxy embedded in an E5 background (example: NGC 5078)
Edge-on gal. |SA(rl,nrl,nb)0^+^/E(d)0 |An inclined disk with multiple features embedded within an E0 background (example: NGC 1553)
Other        |Pec                     |A peculiar galaxy, a significantly disturbed interacting system that cannot be classified in any other way; typically an ongoing or advanced merger or other disturbed type of system (examples: NGC 520, 4038-9)
Other        |pec                     |In a classification, this refers to a classifiable galaxy having some peculiarity (such as some types of asymmetry; examples: NGC 1087, 1097)
Other        |Dark-spacer             |A galaxy which shows a distinctive area or areas of lower surface brighter within the bright part of a disk (Buta 2014ASPC..480...53B). In some early-type galaxies, the appearance of an inner ring may be defined mainly by a subtle darker area around a bar (Laurikainen et al. 2013MNRAS.430.3489L; example: NGC 2787)
Other        |Counter-winding spiral  |A spiral galaxy having two sets of spiral structure which wind outward in opposite senses
Other        |a                       |Examples are all based on Table 6 mean classifications.
Other        |b                       |Previously called catastrophic rings by Buta (2013pss6.book....1B)
Other        |c                       |For other combinations, see Table 6.