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oocyte vs. ovum

[oh-uh-sahyt] / ˈoʊ əˌsaɪt /

noun

Cell Biology.
  1. an immature egg cell of the animal ovary; in humans, one oocyte matures during the menstrual cycle, becoming an ootid and then an ovum, while several others partially mature and then disintegrate.

[oh-vuhm] / ˈoʊ vəm /

noun

plural

ova
  1. Cell Biology.

    1. the female reproductive cell or gamete of animals, which is capable of developing, usually only after fertilization, into a new individual.

    2. the female reproductive cell or gamete of plants.

  2. Architecture. an oval ornament, as in an egg-and-dart molding.