Translates something like "egg-live-bearing".
A type of reproduction, somewhere between laying eggs and bearing live young in the way placental Mammals do. In this variant an egg-like structure is made, but it is fertilised inside the mother (unlike most fish), where it is kept untill it hatches (unlike true egglaying animals).
Explained this way, it might seem that there is little difference between ovovivipare animals and placental mammals. The big difference however, is that in placental mammals there is a constant exchange between mother and fetus through the placenta. Waste is efficiently removed, and a constant supply of nutrients and oxygenis provided. In the ovovivipare situation, all supplies that the embryo needs have to be stored inside the "egg" as it is made, and all waste products stay inside untill the child is ready to hatch.
Ovovivipary is thought to have evolved in exothermic animals as an adaptation to colder climats. Since the eggs are held inside the maternal body, she can easily keep them warm by keeping herself warm (either by searching out warm places or by shivering). This gives these animals the ability to go inhabit areas where traditional egglayers cannot reproduce anymore.
Examples of ovovivipare animals are found in reptiles, fish and insects