Cil"i*a (?), n. pl. Cilium, the sing., is rarely used. [L. cilium eyelid.]
Small, generally microscopic, vibrating appendages lining certain organs, as the air passages of the higher animals, and in the lower animals often covering also the whole or a part of the exterior. They are also found on some vegetable organisms. In the Infusoria, and many larval forms, they are locomotive organs.
Hairlike processes, commonly marginal and forming a fringe like the eyelash.
Small, vibratory, swimming organs, somewhat resembling true cilia, as those of Ctenophora.
© Webster 1913.