trichoepithelioma /trik′ō·ep′ithē′lē·ō″mə/ pl. trichoepitheliomas, trichoepitheliomata [Gk, thrix + epi, above, thele nipple, oma, tumor] , a cutaneous tumor derived from the basal cells of the follicles of fine body hair. One form of trichoepithelioma is an inherited condition and usually occurs as multiple growths. Also called acanthoma adenoides cysticum, epithelioma adenoides cysticum.