viviparity
quality of giving birth to live young in animals, or, in plants, seeds or embryos that begin to develop before they detach from the parent
en-US/ˌvɪvəˈpæɹɪti/
en-GB/vɪvɪpæɹɪtiː/
quality of giving birth to live young in animals, or, in plants, seeds or embryos that begin to develop before they detach from the parent