moth·er·fuck·er /ˈmʌðəˌfʌkə $ -ðərˌfʌkər/ noun [countableC] American EnglishAmE taboo spokenDON'T LIKEINSULT a very offensive word for someone that you dislike very much or that you are very angry with. Do not use this word. 混账东西,杂种 —motherfucking adjectiveadj