From Longman Dictionary of Contemporary Englishflukefluke /fluːk/ noun [countable] informalCHANCE/BY CHANCEsomething good that happens because of luckHe agreed that the second goal was a fluke. —fluky, flukey adjectivea fluky winExamples from the Corpusfluke• Unconsciously we feel it was a fluke and we are afraid of being found out.• I'll have to win more than once, otherwise people will think it was a fluke.• This was a fluke, a one-timeloophole that has been plugged.• But there was no fluke, and no mistake, about what happened here Sunday.• By some terrificfluke Richard came face to face with his future at the precise time he most needed to see it.Originfluke(1800-1900) Origin unknown.