noun Uncommon

firefly

FEYE-uh-fleye

Firefly (noun) means a small beetle that glows in the dark, especially at dusk. Example: “The kids ran through the yard catching fireflies in jars.”

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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

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C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

Word forms

fireflies plural

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Etymology

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

Synonyms

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fire beetle lightning bug

Rhymes for firefly

chiefly briefly

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Frequently asked questions

What does “firefly” mean?

The word “firefly” means a small beetle that glows in the dark, especially at dusk. In plain terms, a glowing beetle seen on summer nights.

How do you pronounce “firefly”?

“Firefly” is pronounced FEYE-uh-fleye (/ˈfaɪ.ɚˌflaɪ/ in IPA).

How do you use “firefly” in a sentence?

Here is “firefly” used in a sentence: “The kids ran through the yard catching fireflies in jars.”

What part of speech is “firefly”?

“Firefly” is a noun.

Is “firefly” a common word?

“Firefly” is an uncommon word in modern English.