Pronunciation: (mon'stur), [key]
1. a legendary animal combining features of animal and human form or having the forms of various animals in combination, as a centaur, griffin, or sphinx.
2. any creature so ugly or monstrous as to frighten people.
3. any animal or human grotesquely deviating from the normal shape, behavior, or character.
4. a person who excites horror by wickedness, cruelty, etc.
5. any animal or thing huge in size.
a. an animal or plant of abnormal form or structure, as from marked malformation or the absence of certain parts or organs.
b. a grossly anomalous fetus or infant, esp. one that is not viable.
7. anything unnatural or monstrous.
huge; enormous; monstrous: a monster tree.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.