gamma moth

noun

: a migratory European noctuid moth (Plusia gamma) having a bright silvery Y-shaped mark on each of the forewings and a larva that feeds on the cabbage and other vegetables

called also silver Y moth

Word History

Etymology

New Latin gamma (specific epithet of Plusia gamma), from Late Latin, third letter of the Greek alphabet; from the likeness in shape of the marks on the forewings to small gammas

First Known Use

1799, in the meaning defined above

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