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Added 9 October 2026

firefly

/ˈfaɪ.əˌflaɪ/ noun

In Latin: cicindēla Wiktionary

noun Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about firefly at Wordnik → Where our words come from →

Tropical American click beetle having bright luminous spots.
Nocturnal beetle common in warm regions having luminescent abdominal organs.

Origin

Endocentric compound of fire + fly, because the insects glow; whence also lightning bug. Compare glow fly, glowworm, and lanternfly. Compare typologically Ancient Greek λαμπυρίς (lampurís, “glowworm”) (<+ πῦρ (pûr)).

From Wiktionary, via Kaikki.org (CC BY-SA)

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