1. A body form of a cnidarian, such as a hydra or coral, that is cylindrical in shape, has a mouth usually surrounded by tentacles at one end, and is often attached to something at the other end.
2. A usually nonmalignant growth or tumor protruding from the mucous lining of an organ such as the nose, bladder, or intestine, sometimes causing obstruction.
[Middle English polip, nasal tumor, from Old French polipe, from Latin pōlypus, cuttlefish, nasal tumor, from Greek polupous, poulupous : polu-, poly- + pous, foot; see ped- in the Appendix of Indo-European roots.]
(click for a larger image)polyp
pedunculate polyp (top) and sessile polyp (bottom) in a section of large intestine
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.