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fly - definition and synonyms


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noun [countable] fly pronunciation in American English /flaɪ/
Word Forms
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  1. 1
    a common small insect with wings. Flies eat food, are often found near garbage, and are responsible for spreading many diseases

    A trapped fly buzzed against the window pane.

    a swarm/cloud/plague of flies:

    There were clouds of small flies over the river.

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  2. 2
    the opening at the front of a pair of pants that is fastened with buttons or a zipper. The British word is flies

    Your fly is open!

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a title used before a man or woman's name as a gender-neutral alternative to Mr, Ms, etc

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another way of saying congratulations, or that something/someone looks nice or fascinating

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