fol·li·cle / ˈfälikəl/ • n. 1. Anat. a small secretory cavity, sac, or gland, in particular: ∎  (also hair follicle) the sheath of cells and connective tissue that surrounds the root of a hair. ∎ short for Graafian follicle.2. Bot. a dry fruit that is derived from a single carpel and opens on one side only to release its seeds.DERIVATIVES: fol·lic·u·lar / fəˈlikyələr/ adj.fol·lic·u·late / fəˈlikyələt; -ˌlāt/ adj.fol·lic·u·lat·ed / fəˈlikyəˌlātid/ adj.ORIGIN: late Middle English: from Latin folliculus ‘little bag,’ diminutive of follis ‘bellows.’

follicle
1. (in animal anatomy) Any enclosing cluster of cells that protects and nourishes a cell or structure within. For example, follicles in the ovary contain developing egg cells, while hair follicles envelop the roots of hairs.

2. (in botany) A dry fruit that, when ripe, splits along one side to release its seeds. It is formed from a single carpel containing one or more seeds. Follicles do not occur singly but are grouped to form clusters (etaerios). Examples include larkspur, columbine, and monk's hood.

follicle (fol-ikŭl) n. a small secretory cavity, sac, or gland. See also Graafian follicle, hair (follicle).
—follicular (fŏ-lik-yoo-ler) adj.

follicle A dry fruit derived from a single carpel which dehisces along one side only.

follicle (anat., etc.) small sac. XVII. — L. folliculus little bag, dim. of follis bellows; see -CLE.