Pronunciation: (hī'lum),[key] —n., —pl.-laPronunciation: (-lu).[key] 1. Bot. a. the mark or scar on a seed produced by separation from its funicle or placenta.
b. the nucleus of a granule of starch.
2. Mycol.a mark or scar on a spore at the point of attachment to the spore-bearing structure.
3. Anat.the region at which the vessels, nerves, etc., enter or emerge from a part.