|nucellus (n-sěl'əs) Pronunciation Key
Plural nucelli (n-sěl'ī)
The megasporangium of a seed-bearing plant, located in the ovule. In angiosperms, it is the central portion of the ovule in which the embryo sac develops. In some cases of apomixis (production of seeds without fertilization), cells of the nucellus develop into an embryo.