glowworm

[ gloh-wurm ]
/ ˈgloʊˌwɜrm /

noun

the wingless female or larva of the European beetle, Lampyris noctiluca, which emits a sustained greenish light.
any of various other beetle larvae or wingless females that emit a glow rather than a flash of light.

Origin of glowworm

1300–50; Middle English. See glow, worm
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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