Caeruleus -eous: light sky-blue [between lavender and cobalt blue] = coeruleus.
Caerulescent: with a tinge of sky-blue.
Caesius -eous: a pale dull blue-gray [blue-gray].
Caespiticolous: frequenting or living in grassy pastures or lawns.
Calathiform: shaped like a deep bowl.
Calcar -ium; pl. ia: a movable spur or spine-like process: specifically the spines at the apex of a tibia.
Calcarate -us: with a movable spur or spine-like process.
Caliciform: shaped like a cup or calyx.
Calipers: the anal forceps in Dermaptera.
Calli axillary: Odonata; thickenings at the bases of the wings; distinguished as anterior at the base of the costa, and posterior at the base of radius + medius and cubitus: = axillary calli.