Is it farther or further?
early 15c., from French follicule or directly from Latin folliculus "little bag," diminutive of follis "bellows, inflated ball," from PIE *bhol-n-, suffixed form of root *bhel- (2) "to blow, swell" (see bole).
follicle fol·li·cle (fŏl'ĭ-kəl)
A small bodily cavity or sac.
A crypt or minute cul-de-sac or lacuna, such as the depression in the skin from which the hair emerges.
An ovarian follicle.
A spherical mass of cells usually containing a cavity.