1. <zoology> Any one of numerous species of long-winged, migratory, orthopterous insects, of the family Acrididae, allied to the grasshoppers; especially, (Edipoda, or Pachytylus, migratoria, and Acridium perigrinum, of Southern Europe, Asia, and Africa. In the United States the related species with similar habits are usually called grasshoppers. See Grasshopper.

These insects are at times so numerous in Africa and the south of Asia as to devour every green thing; and when they migrate, they fly in an immense cloud. In the United States the harvest flies are improperly called locusts. See Cicada. Locust beetle, an African bird; the beefeater.

2. [Etymol. Uncertain.

<botany> The locust tree. See Locust Tree (definition, note, and phrases).

<botany> Locust bean, a commercial name for the sweet pod of the carob tree.

Origin: L. Locusta locust, grasshopper. Cf. Lobster.

(01 Mar 1998)