thoroughly Syllabification: (thor·ough·ly)Pronunciation: /ˈTHərōlē/Translate thoroughly | into French | into German | into Italian | into Spanish Definition of thoroughly adverb 1in a thorough manner:he searched the house thoroughly 2very much; greatly:I thoroughly enjoyed the day [as submodifier]:she was soon thoroughly boredthoroughly in other Oxford dictionaries Definition of thoroughly in the British & World English dictionary