noun

firefly

FEYE-uh-fleye

noun

A small beetle that glows in the dark, especially at dusk.

"The kids ran through the yard catching fireflies in jars."

"On summer evenings the field lit up with fireflies."

How to Use Firefly

Learner’s notes

In plain EnglishA glowing beetle seen on summer nights.

Common pairings

catch fireflies firefly glow

fireflies plural

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A compound of fire and fly, named for the insect's glow; related terms include lightning bug and glowworm.

chiefly briefly