Pronunciation: (tu-pē'tum), [key]
—pl. -taPronunciation: (-tu). [key]
1. Bot.a layer of cells often investing the archespore in a developing sporangium and absorbed as the spores mature.
2. Anat., Zool.any of certain membranous layers or layered coverings, as in the choroid of the eyes of certain animals.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.