Graafian adj. (Anat.) Pertaining to, or discovered by, Regnier de Graaf, a Dutch physician.
Graafian follicles or vesicles, small cavities in which the ova are developed in the ovaries of mammals, and by the bursting of which they are discharged.
... few days, and is merely the critical period in a monthly cycle or periodicity which goes with the female sex specialization. This period involves the gradual preparation of the uterus or womb for a guest, together with the maturing of the ova. Then the Graafian follicles containing the ova break and these latter enter the uterus ... — Taboo and Genetics • Melvin Moses Knight, Iva Lowther Peters, and Phyllis Mary Blanchard