Sirloin is chewier than filet and has more marbling.
Tips
usage
Phonetic loan from English 'sirloin'. Beef-cut vocabulary in Chinese is largely loaned: 西冷 sirloin, 菲力 filet/tenderloin, 肉眼 (sometimes 眼肉) ribeye, 丁骨 T-bone, 战斧 tomahawk. 西冷 without 牛排 still means the sirloin cut in a steakhouse context.
