Pronunciation IPA (key): /ˈfæktɔɪd/ Audio (UK)(file) Noun Singular factoid Plural factoids (countable) A factoid is something that sounds like it is a true, or something that people say is true, but it is not. Einstein did not fail math--that is a factoid! (countable) A factoid is a bit of trivia--a small fun fact. Would you like to hear a cool factoid?Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads