beef loin; beef sirloin; beef roast
Refers to cuts from the beef loin area, often used for roasting or as sirloin. In culinary contexts, 牛ロース can mean a roast or a sirloin cut.
Tonight's dinner is roast beef made from beef loin.
I bought a block of beef sirloin at the supermarket.
Compound of 牛 (ぎゅう, 'beef') and ロース, from English 'roast' or 'loin', referring to beef loin/roast cuts.