Coecal: ending blindly, or in a closed tube or pouch.
Coecum: a blind sac or tube: applied to a series of appendages opening into the alimentary canal at the junction of the gizzard and chylific ventricle: see caecum; the two are used interchangeably.
Coeloblast: the endoderm in the narrower sense.
Coelom: the body cavity.
Coelomic cavity: the space between the viscera and the body wall.
Coelom-sac: the cavity containing the viscera: in embryology one of a pair of closed sacs, arising in the mesoderm of each segment of the embryo and giving rise to more or less of the coelom of the adult.
Coenogonous: oviparous at one season of the year, ovoviviparous at another, as in Aphididae.
Coeruleus -eous: sky-blue: see caeruleus.
Coincident: when two wing veins run together or lie, one in continuation of the other so as to appear like one.
Coleoptera: sheath-winged: an order with the primaries coriaceous, used as a cover only, meeting in a straight line dorsally; mouth mandibulate; pro-thorax free; transformation complete: the beetles: the term has also been applied to the two elytra together.
Collar: in general any structure between the head and thorax: specifically, in Hymenoptera, the neck; in Diptera, may mean the neck, the sclerites attached to the thorax, the thorax itself, or its processes (ante furca): in Coleoptera, is the narrowed thorax; in Lepidoptera, applied to the sclerites attached to the thorax and which shield the neck.
Collembola: an ordinal term applied to species which are apterous; have no metamorphoses; have variably developed abdominal saltatorial appendages and a peculiar ventral tube at base: the spring-tails.
Colleterial gland: see Colleterium.
Colleterium: a glandular structure accessory to the oviduct, secreting the viscid material used in cementing the eggs together.
Collophore: the sucker-like organ extended from the underside of the abdomen in Collembola.
Collum: the neck or collar: the slender connection between head and thorax in Hymenoptera and Diptera; in Coleoptera, the posterior, narrow part of the head or even the thorax: loosely used.
Colon: the large intestine; that usually enlarged portion of the alimentary canal before the rectum.
Columella: a little rod, pillar or central axis.
Columnar: cylindric, but tapering toward one end.
Comate -us: only the upper part of head, or vertex, covered with hair. Commensal: one who eats at another's table: applied to species that feed on the surplus supply of another, without destroying the owner of the supply.
Commensalism: applied to this manner of living and eating together.
Comminute: to grind up fine: to reduce to minute particles.
Commissure: the nerves connecting two ganglia: the point of meeting or union of two bodies: a bridge connecting two bodies or structures; e.g. tracheal tubes.
Common: of frequent occurrence: occurring on two adjacent parts: a band or fascia is common when it crosses both primaries and secondaries.
Communal: applied to life or dwelling in colonies like ants and bees.
Comose: ending in a tuft or brush.
Complanate: compressed: flattened above and below: = deplanate.
Complemental: applied to sexed forms in the Termitidae, capable of reproduction, but which do not reach the winged stage; the females are less fertile than the forms that become winged and several may be used in one nest to replace a lost queen or mature female.
Explanation of Terms Used in Entomology · The Wunder Library — complete classics, free to read, with narration.