from The Century Dictionary and Cyclopedia
- n. A meroblastic egg, ovum, or ovule which has acquired its store of foodyolk, or been otherwise modified from its original primitive condition as an egg-cell or protovum. Also called after-egg and deutovum.
Sorry, no etymologies found.
In this way the ovum enters on its second stage (the metovum), which is many times larger than the first, but still only a single enlarged cell.