sirloin Syllabification: (sir·loin)Pronunciation: /ˈsərloin/Translate sirloin | into French | into German | into Italian | into Spanish Definition of sirloin noun the choicer part of a loin of beef: [as modifier]:fresh sirloin steaksOrigin: late Middle English: from Old French (see sur-1, loin)sirloin in other Oxford dictionaries Definition of sirloin in the British & World English dictionary