n.1 any of various African and Asian grasshoppers of the family Acrididae, migrating in swarms and destroying vegetation.
2 US a cicada.
3 (in full locust bean) a carob.
4 (in full locust tree) a a carob tree. b ACACIA 2. c KOWHAI.
Phrases and idioms:
locust-bird (or -eater) any of various birds feeding on locusts.
Etymology: ME f. OF locuste f. L locusta lobster, locust