1N-UNCOUNT 羊肉Mutton is meat from an adult sheep that is eaten as food. 羊肉
...a leg of mutton.
羊腿
...mutton stew.
炖羊肉
2PHRASE 装嫩的女人 If you describe a woman as mutton dressed as lamb, you are criticizing her for trying to look younger than she really is, in a way that you consider unattractive. 装嫩的女人 [British, informal, disapproval]