Cyaneous: pure dark blue: indigo blue [French blue].

Cyanescent: with a deep bluish tinge or shading.

Cyanogenic: applied to repugnatorial glands in myriapods and sometimes in insects.

Cyathiform: obconical and concave; cup-shaped: = cupuliform.

Cyatotheca: the cover of the thorax in the pupa.

Cycle: a round or circle, e.g. of development; a life cycle.

Cyclorrhapha: that section of Diptera in which the adult escapes from the hardened pupal case by pushing off a lid or covering: see orthorrhapha. Cyclorrhaphous: circular seamed.

Cydariform: globose, but truncated at two opposite sides.

Cylindrical: in the form of a cylinder or tube; round, elongate, of equal diameter throughout.

Cymbiform: boat-shaped: a concave disc with elevated margin; navicular.