Pro*em"bry*o (?), n. [Pref. pro- + embryo. ] Bot. (a)
The series of cells formed in the ovule of a flowering plant after fertilization, but before the formation of the embryo.
(b)
The primary growth from the spore in certain cryptogamous plants; as, the proembryo, or protonema, of mosses.
© Webster 1913.