Firefly

How to spell firefly

7 letters · 3 syllables

How to pronounce firefly

Say the part in capitals loudest.

What does firefly mean?

1. nounA small nocturnal beetle that produces a glowing light from its abdomen to attract a mate.

Firefly in a sentence

• A single firefly blinked on and off above the dark lawn.

• The children tried to catch a firefly in a glass jar at dusk.

Where does firefly come from?

Language of origin: Germanic

Firefly is a transparent English compound, simply joining 'fire' and 'fly', and it has been used since the 1650s for the small nocturnal beetle whose tail gives off a cold, greenish glow. The 'fire' element descends from Old English fyr, the word for flame or burning, while 'fly' comes from Old English fleoge, a general name for a flying insect rather than the true house fly we picture today. The name captures the way the insect seems to carry a tiny living flame as it drifts through the dark. Despite the name, a firefly is not a fly at all but a beetle of the family Lampyridae, a Latin name itself rooted in the Greek lampein, meaning 'to shine'. Because both halves are familiar everyday words, the spelling is straightforward; the only thing to watch is keeping it as a single closed word rather than two.

How the word is built

• fire (Old English fyr: flame, burning)
• fly (Old English fleoge: a flying insect)