Simple Definition of gadfly

from our Learner's Dictionary

gadfly

noun

ˈgædˌflaɪ

plural gadflies

: someone who annoys people by being very critical

a political gadfly [=a person who criticizes politicians, political decisions, etc.]

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“Gadfly.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/gadfly. Accessed 21 Jun. 2026.

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