Collins English-English Dictionary

locust ['ləυkəst]

1. 1. n any of numerous orthopterous insects of the genera Locusta, Melanoplus, etc, such as L. migratoria, of warm and tropical regions of the Old World, which travel in vast swarms, stripping large areas of vegetation - See also grasshopper - Compare seventeen-year locust

2. 2. n locust tree false acacia a North American leguminous tree, Robinia pseudoacacia, having prickly branches, hanging clusters of white fragrant flowers, and reddish-brown seed pods

3. 3. n the yellowish durable wood of this tree

4. 4. n any of several similar trees, such as the honey locust and carob

5. 5. n [Etymology] C13 (the insect): from Latin locusta locust; applied to the tree (C17) because the pods resemble locusts