A sirloin is a piece of beef which is cut from the bottom and side parts of a cow's back. sirloin steaks. a good quality piece of beef which is cut from the lower part of a cow's back (surlonge, from sur + loigne, longe ( LOIN))
() Middle English surloine, from Old French surlonge, from sur la longe, “above the loin”.“” in Dictionary.com Unabridged, v1.0.1, Lexico Publishing Group, 2006.