Cilia: The fine hairlike projections from certain cells such as those in the respiratory tract that sweep in unison and help to sweep away fluids and particles. Some single-celled organisms use the rhythmical motion of cilia for locomotion.
Cilia is the plural of cilium, a Latin word referring to the edge of the eyelid and, much later, to the eyelashes. Cilia came to be known fine hairlike projections from cells.
Quick GuideCommon Eye Problems and Infections
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