- A fine hairlike projection from a cell such as those in the respiratory tract. Cilia can help to sweep away fluids and particles. Some single-celled organisms use the rhythmical motion of cilia for locomotion. Cilium is Latin. It referred to the edge of the eyelid and, much later, to the eyelashes. In the same sense, cilia came to refer to the fine hairlike projections from cells.
* * *1. [NA] SYN: eyelash. 2. A motile extension of a cell surface, e.g., of certain epithelial cells, containing nine longitudinal double microtubules arranged in a peripheral ring, together with a central pair. [L. an eyelid]
* * *1) EYELASH2) a minute short hairlike process often forming part of a fringe esp one of a cell that is capable of lashing movement and serves esp. in free unicellular organisms to produce locomotion or in higher forms a current of fluid
* * *n. (pl. cilia)1. a hairlike process, large numbers of which are found on certain epithelial cells and on certain (ciliate) protozoa. Cilia are particularly characteristic of the epithelium that lines the upper respiratory tract, where their beating serves to remove particles of dust and other foreign material.2. an eyelash or eyelid.• ciliary adj.
* * *cil·i·um (silґe-əm) [L.] singular of cilia.
Medical dictionary. 2011.