The following is a glossary of common English language and scientific terms used in the description of gastropods.
Abapical – away from the apex of a shell toward the base
Acephalous – Headless.
Acinose – Full of small bulgings; resembling the kernel in a nut.
Aculeate – Very sharply pointed, as the teeth on the radula of some snails.
Acuminate – gradually tapering to a point, as the spire of some shells.
Acute – Sharp or pointed, as the spire of a shell, or the lip of a shell.
Adapical – toward the apex of a shell (↔ abapical)
Admedian – Next to the central object, as the lateral teeth on the lingual membrane.
Adpressed – with overlapping whorls or with a suture tightly pressed to the previous whorl (preferred to the term appressed)
Afferent – To bring in; when relating to a vessel or duct, indicating that it brings in its contents.
Amoeboid – Shaped like an amoeba, a small animalcule.
Amorphous – Without distinct form.
Amphibious – Inhabiting both land and water.
Amphidetic – With the ligament on both sides of the umbones.
Anal canal – Tubular of gutter-like opening in the shell of a gastropod through which excrements are expelled (see also: siphonal canal)
Analogue – A likeness between two objects when otherwise they are totally different, as the wing of a bird and the wing of a butterfly.
Anastomosing – Coming together.
Annular – Made up of rings.
Anterior – The front or fore end.
Aquatic – Inhabiting the water.
Arborescent – Branching like a tree.
Arched – Bowed or bent in a curve.
Arcti-spiral – Tightly coiled, as some spiral shells.
Asphyxiating – Causing suspended animation; apparent death.
Assimilation – Act of converting one substance into another, as the changing of food-stuffs into living bodies.
Asymmetrical – Not symmetrical.
Atrium
Atrophied – Wasted away.
Attenuate – Long and slender, as in some shells.
Auditory – Connected with the hearing.
Auricled – Eared, or with ear-like appendages.
Basal – The bottom or lower part.
Biangulate – With two angles.
Bicuspid or bicuspidate – Having two cusps.
Bifid – Having two arms or prongs.
Bifurcated – Having two branches.
Bilateral – With two sides.
Bilobed – With two lobes.
Blood sinus
Bulbous – Swollen.
Calcareous – Composed of carbonate of lime.
Callosity – A hardened and raised bunch, as the callus on the columella of some shells.
Callus – A deposit of shelly matter.
Campanulate – Formed like a bell.
Canaliculate – Resembling a canal, as the deep sutures in some shells.
Cancellated – Formed of cross-bars, as the longitudinal and spiral lines which cross in some shells.
Cardiac pouch – Containing the heart and placed near the umb'ones of the shell.
Carinate – Keeled. With keel.
Cartilaginous – Like cartilage.
Caudal – Tail-like, or with a tail-like appendage.
Cellular – Made up of cells.
Cerebral – Pertaining to the brain.
Channeled – Grooved or formed like a channel.
Chitinous – Formed of chitin, as the radulas of gastropods.
Ciliary – By means of cilia.
Ciliated – Having cilia.
Cilium (plural cilia) – A lash; used to designate the hairs on the mantle, gills, etc.
Clavate – Club-shaped.
Coarctate – Pressed together, narrowed.
Concave – Excavated, hollowed out.
Conchiolin
Conic – Shaped like a cone.
Connective – A part connecting two other parts, as a muscle connecting two parts of the body, or a nerve connecting two ganglia.
Constricted – Narrowed.
Contractile – Capable of being contracted or drawn in, as the tentacle of a snail.
Convex – Bulged out, as the whorls of some snails.
Convoluted – Rolled together.
Cordate – Heart-shaped.
Corneous – Horn-like, as the opercula of some gastropods.
Corrugated – Roughened by wrinkles.
Costate – Having rib-like ridges.
Crenulate – Wrinkled on the edges.
Crescentic – Like a crescent.
Cylindrical – Like a cylinder.
Decollated – Cut off, as the apex of some shells.
Decussated – With spiral and longitudinal lines intersecting, as the sculpture of some shells.
Deflexed – Bent downward, as the last whorl in some snails.
Dentate – With points or nodules resembling teeth, as the aperture of some snails.
Denticulate – Finely dentate.
Depressed – Flattened, as the spire in some snails.
Dextral – Right-handed.
Digitiform – Finger-like.
Dilated – Expanded in all directions, as the aperture of a shell.
Dimorphism – With two forms or conditions.
Dioecious – Having the sexes in two individuals, one male and one female.
Distal – The farthest part from an object.
Discoidal – Shaped like a flat disk.
Diverticulum – A pouch or hole, as the pouch containing the radula, or that containing the dart in helices.
Dormant – In a state of torpor or sleep.
Dorsal – The back. In gastropods the opposite to the aperture.
Ectocone – The outer cusp on the teeth of the radula.
Edentulous – Without teeth or folds, as the aperture in some gastropods.
Efferent – Carrying out.
Elliptical – With an oval form.
Elongated – Drawn out, as the spire of a shell.
Emarginate – Bluntly notched.
Encysted – Enclosed in a cyst.
Entocone – The inner cusp on the teeth of the radula.
Entire – With even, unbroken edges, as the aperture of some shells.
Epiphallus – A portion of the vas deferens which becomes modified into a tube-like organ and is continued beyond the apex of the penis; it frequently bears a blind duct, or flagellum.
Epithelium – All tissues bounding a free surface.
Equidistant – Equally spaced, as the spiral lines on some snail shells.
Equilibrating – Balancing equally.
Eroded – Worn away, as the epidermis on some shells.
Erosive – Capable of erosion.
Excavated – Hollowed out, as the columella of some snails.
Excurrent – Referring to the siphon which carries out the waste matter of the body.
Exoskeleton – The outer skeleton; all shells are exoskeletons.
Exserted – Brought out.
Expanded – Spread out, as the lip of some shells.
Falcate – Scythe-shaped.
Fasciculus – A little bundle.
Flagellate – Animals with a flagellum or lash.
Flexuous – Formed in a series of curves or turnings, as the columella in some shells.
Flocculent – Clinging together in bunches.
Fluviatile – Living in running streams.
Fusiform – Thick in the middle and tapering at each end.
Gelatinous – Like jelly, as the eggs of some mollusks.
Gibbous – Very much rounded, as the whorls in some snails.
Glandular – Like a gland.
Globose – Rounded.
Granulated – Covered with little grains.
Gravid – A female mollusk with ovaries distended with young.
Gregarious – Living in colonies.
Gular – Relating to the windpipe or palate. In mollusks, referring to the innermost part of the aperture.
Habitat – Locality of a species.
Hasmolymph – Molluscan blood.
Heliciform – In form like Helix.
Hemispherical – Half a sphere.
Herbivorous – Subsisting upon vegetable food.
Hermaphrodite – Having the sexes united in the same individual.
Hibernation – The act of hibernating or going to sleep for the winter months.
Hirsute – Covered with hairs, as some snails.
Hispid – Same as hirsute.
Homologous – Having the same position or value, as the wing of a bird and of a bat.
Hyaline – Glassy.
Imperforate – Not perforated or umbilicated.
Impressed – Marked by a furrow, as the impressed spiral lines on some gastropod shells.
Incrassate – Thickened.
Incurved – Leaned or bent over, as the apex in some snails.
Indented – Notched.
Inflected – Turned in, as the teeth of some snails.
Inhalent – Same as incurrent.
Inoperculate – Without an operculum.
Intercostate – Between the ribs or ridges.
Invaginate – One part bending into another, as the tentacles of some land snails.
Invertible – Capable of being inverted, or drawn in, as the eye-peduncles of a land snail.
Juvenile
Keeled – With a more or less sharp projection at the periphery.
Lamellated – Covered with scales.
Lamelliform – Having the form of scales.
Laminated – Consisting of plates or scales laid over each other.
Lanceolate – Gradually tapering to a point.
Lateral – Pertaining to the side.
Latticed – (See decussated.)
Lobulate – Composed of lobes.
Longitudinal – The length of a shell.
Lunate – Shaped like a half moon, as the aperture in some shells.
Malleated – Appearing as though hammered.
Manducatory – Relating to the apparatus for masticating food. In snails, the jaws and radula.
Median – Middle, as the middle tooth on the radula.
Mesocene – The middle cusp on the teeth of the radula.
Monoecius – Having the sexes united in the same individual.
Multifid – Made up of many lobes or projections, as the cusps on some radulae.
Multispiral – Consisting of many whorls, as some fresh-water snails.
Nacreous – Pearly or iridescent.
Nepionic – The second stage of the embryonic shell, as the glochidium.
Notched – Nicked or indented, as the anterior canal of some gastropods.
Nucleus – The first part or beginning, as the apex in a gastropod shell.
Nucleated – Having a nucleus.
Obconic – In the form of a reversed cone.
Oblique – Slanting, as the aperture of some shells when not parallel to the longitudinal axis.
Obovate – Reversed ovate, as some shells when the diameter is greater near the upper than at the lower part.
Obtuse – Dull or blunt, as the apex of some gastropods.
Olfactory – Pertaining to the smell.
Olivaceous – Colored like an olive.
Organism – An organized being, or living object made up of organs.
Ovate – Egg-shaped.
Ovately conic – Shaped like an egg, but with a somewhat conic apex, as some gastropods.
Oviparous – Bringing forth young in an egg which is hatched after it is laid.
Ovisac – A pouch in which the eggs or embryos are contained.
Ovoviviparous – In this case the young are formed in an egg but are hatched inside the parent.
Pallial lung
Papillose – Covered with many little bulgings or pimples.
Parallel – Having the same relative distance in all parts, as when the spiral lines in univalve shells are the same distance apart all the way around.
Patelliform – Shaped like a flattened-out cone, as an Ancylus.
Patulous – Open and spreading, as the aperture in some gastropods.
Paucispiral – Only slightly spiral, as some opercula.
Pectinate – Like the teeth of a comb, as the gills of some mollusks.
Pedal – Pertaining to the foot.
Pedunculated – Supported on a stem or stalk, as the eyes of land snails.
Pellucid – Transparent or clear, as the shells of some snails; e. g. Vitrea.
Penultimate – The whorl before the last in gastropod shells.
Pericardium – The chamber containing the heart.
Periostracum – The epidermal covering of some shells.
Pervious – Very narrowly open, as the umbilicus in some snails.
Phytophagus – Vegetable-feeding.
Pilose – Covered with hairs.
Pinnate – Branched like a feather, as the gills of some mollusks.
Plaited – Folded.
Planispiral shell
Planorboid – Flat and orb-like, as some snails.
Pleurae – Relating to the side of a body.
Plexus – A network of vessels, as the form of the lungs in snails.
Plicated – Made up of folds.
Plumose – Resembling plumes.
Polygonal – Having many angles.
Porcellanous – Like porcelain.
Prismatic – Like a prism.
Prodissoconch – The embryonic shell.
Protoconch – The embryonic shell.
Protract – To push out.
Protractor pedis – The foot protractor muscle.
Protrusile – Capable of being pushed out.
Proximal – The nearest end of an object.
Pulsation – A throb, as the throbbing of the heart.
Pupiform – Like a pupa; one of the stages in the development of an insect.
Pustulate – Covered with pustules or little pimples.
Pustulose – Same as pustulate.
Pyramidal – Having the form of a pyramid.
Pyriform – Shaped like a pear.
Reflected – Bent backward, as the lip in some snails.
Reflexed – Same as Reflected.
Renal – Relating to the kidneys.