black·​fly | \ ˈblak-ˌflī How to pronounce blackfly (audio) \
plural blackflies or blackfly

Definition of blackfly

: any of various small dark-colored insects especially : any of a family (Simuliidae and especially genus Simulium) of bloodsucking dipteran flies whose larvae usually live in flowing streams

Examples of blackfly in a Sentence

Recent Examples on the Web Bug Shirt Untreated loose-knit fabrics provide no defense from mosquitoes, blackflies, and ticks. Andrew Skurka, Outside Online, "How to Pack for a Hike," 21 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'blackfly.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of blackfly

15th century, in the meaning defined above

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The first known use of blackfly was in the 15th century

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Cite this Entry

“Blackfly.” The Dictionary, Merriam-Webster Inc., Accessed 13 December 2019.

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How to pronounce blackfly (audio)

English Language Learners Definition of blackfly

: a small fly that bites


black·​fly | \ ˈblak-ˌflī How to pronounce blackfly (audio) \
plural blackflies

Medical Definition of blackfly

: any of a family (Simuliidae) and especially genus Simulium of bloodsucking dipteran flies

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Rhyming Dictionary: Words that rhyme with blackfly

Comments on blackfly

What made you want to look up blackfly? Please tell us where you read or heard it (including the quote, if possible).


easily led, controlled, or managed

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