- [Anat] The eyelashes.
- [Biol] 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.
- [Bot] Hairlike processes, commonly marginal and forming a fringe like the eyelash.
- [Zoöl] Small, vibratory, swimming organs, somewhat resembling true cilia, as those of Ctenophora.
Etymology: L. cilium eyelid