Fie is an old cry of anger or disgust at someone — a sharp “how dare you” or “shame on you.” You meet it in Shakespeare and other old plays: “Fie on you!” or “Fie, what a thing to say.” Almost nobody uses it in ordinary talk now, except as a joke, or when someone is pretending to sound old-fashioned. It is not a mild “that’s a bit rude.” It is a flash of moral disapproval, or a stage version of one. Though actually, even in the old plays it can be a bit theatrical, a word you say out loud so the whole room hears your scorn.

哼！／可恥！（古英語感嘆，責罵或不以為然；現在幾乎只在戲劇或開玩笑時出現）