My common sense tells me that once ovulation has occurred and the secondary Oocyte is out of the Ovary ,it should be called an Ovum, but my son's high school biology text book mentions a secondary Oocyte as an ovum, actually in a bracket after secondary Oocyte. It further mentions that once the second polar body is released, the secondary Oocyte becomes haploid Ovum (Ootid). But in some other study materials it is mentioned that the secondary Oocyte undergoes second meiotic division and that the second polar body is formed only after a sperm has entered it and it is then only that a secondary Oocyte becomes an Ovum. So I am confused. Can we call the secondary Oocyte, released by a Graafian follicle, an Ovum or not, especially when it has already been "Ovulated", or shall we wait till the release of second polar body, which happens only after a sperm has entered the secondary Oocyte and a haploid Ovum (Ootid) is formed to call it an Ovum?