A follicle in which the primordial oocyte is surrounded by a single layer of flattened follicular cells. ... (05 Mar 2000) ... 
an immature ovarian follicle that has not undergone recruitment and consists of an oocyte enclosed by a single layer of cells.
Type: Term Definitions: 1. a follicle in which the primary oocyte is surrounded by a single layer of flattened follicular cells.