%oosphere%

n. [ Gr. w, 'o`n an egg + E. sphere. ] [ 1913 Webster ]

1. (Bot.) An unfertilized, rounded mass of protoplasm, produced in an oogonium. [ 1913 Webster ]

☞ After being fertilized by the access of antherozoids it becomes covered with a cell wall and develops into an oospore, which may grow into a new plant like the parent. [ 1913 Webster ]

2. (Bot.) An analogous mass of protoplasm in the ovule of a flowering plant; an embryonic vesicle. Goodale. [ 1913 Webster ]