What is the meaning of Ovum?

The female gamete in animals; the egg cell.

ovum (gamete)

egg (approximately spherical or ellipsoidal body produced by birds, insects, reptiles, and other animals, housing the embryo within a membrane or shell during its development)

egg (edible egg of a domestic fowl; the contents of such an egg or eggs used as food)

ovum (gamete)

Source: wiktionary.org