fi·​do | \ ˈfī-(ˌ)dō How to pronounce fido (audio) \
plural fidos

Definition of fido

: a coin having a minting error

Examples of fido in a Sentence

Recent Examples on the Web Training and fitness center Urban Pooch will have an agility field course, $5 per run, for fidos to show off their skills, jumping, climbing over obstacles and navigating tunnels. Hannah Steinkopf-frank, RedEye Chicago, "Pooches on parade: Celebrate Easter at Horner Park," 29 Mar. 2018 So, please feel free to download and build your own FIDO monitor. Kristian Von Bengtson, WIRED, "Instrumentation of the Sapphire Rocket and Ground Support Equipment — For Download," 12 June 2013

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

First Known Use of fido

1967, in the meaning defined above

History and Etymology for fido

freaks + irregulars + defects + oddities

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Cite this Entry

“Fido.” Dictionary, Merriam-Webster, Accessed 29 Feb. 2020.

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