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.