1ADJ-GRADED [usually ADJ n](眼神、表情或話語)會意的,心照不宣的 A sly look, expression, or remark shows that you know something that other people do not know or that was meant to be a secret. (眼神、表情或話語)會意的,心照不宣的
2ADJ-GRADED 狡猾的;詭詐的 If you describe someone as sly, you disapprove of them because they keep their feelings or intentions hidden and are clever at deceiving people. 狡猾的;詭詐的 [disapproval]