polyp

Concise Oxford English Dictionary © 2008 Oxford University Press:
polyp /ˈpɒlɪp/

▶noun

• 1 Zoology the sedentary form of a coelenterate such as a sea anemone, typically columnar with the mouth uppermost and surrounded by a ring of tentacles. Compare with medusa.

• 2 Medicine a small growth, usually benign and with a stalk, protruding from a mucous membrane.

– derivatives
polypoid adjective & noun,
polypous adjective.

– origin ME: from OFr. polipe, from L. polypus (see polypus).