What do the terms anovulation and ovulation mean?

Terminology. Ovulation refers to the release of an oocyte (egg, ) usually around the mid-cycle, from a woman's ovary. Anovulation simply means the absence of ovulation, or not ovulating. There is a wide range of ovulatory dysfunction between these two extremes, involving ovulations that may be unpredictable, infrequent, and in other ways abnormal.
Ovulation yes or no. Anovulation means that no egg is released. Ovulation means that an egg is released.