gadfly Syllabification: (gad·fly)Pronunciation: /ˈgadˌflī/Definition of gadfly noun (plural gadflies) a fly that bites livestock, especially a horsefly, warble fly, or botfly. an annoying person, especially one who provokes others into action by criticism. Origin: late 16th century: from gad1, or obsolete gad 'goad, spike', from Old Norse gaddr, of Germanic origin; related to yard1gadfly in other Oxford dictionaries Definition of gadfly in the British & World English dictionary
