firefly

play
noun fire·fly \-ˌflī\

Definition of firefly

  1. :  any of various winged nocturnal beetles (especially family Lampyridae) that produce a bright soft intermittent light by oxidation of luciferin especially for courtship purposes

Illustration of firefly

1658

First Known Use of firefly

1658


FIREFLY Defined for English Language Learners

firefly

play
noun fire·fly \-ˌflī\

Definition of firefly for English Language Learners

  • : a small flying insect that produces a soft light


FIREFLY Defined for Kids

firefly

play
noun fire·fly \ˈfīr-ˌflī\

Definition of firefly for Students

plural

fireflies

  1. :  a small beetle producing a soft light



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