Synonym for polyp ... 1. <pathology> Growth, usually benign, protruding from a mucous membrane. ... 2. <plant biology> The sessile stage of the Cnidarian life cycle, the cylindrical body is attached to the substratum at its lower end and has a mouth surrounded by tentacles bearing nematocysts at the upper end, Hydra and the feeding poly... Found on http://www.encyclo.co.uk/local/20973