seventeen-year locust

noun

1. a cicada, Magicicada septendecim, of the eastern U.S., having nymphs that live in the soil, usually emerging in great numbers after 17 years in the North or 13 years in the South.

noun

1. an E North American cicada, Magicicada septendecim, appearing in great numbers at infrequent intervals because its nymphs take 13 or 17 years to matureAlso called: periodical cicada