ugly: [13] Ugly originally meant ‘horrible, frightening’; ‘offensive to the sight’ is a secondary development, first recorded in the 14th century. The word was borrowed from Old Norse uggligr, a derivative of the verb ugga ‘fear’. In the early 1930s it was applied, in the altered spelling ugli, to a new sort of citrus fruit, a hybrid of the grapefruit and the tangerine; the reference is to the fruit’s unprepossessing knobbly skin. [ugly etymology, ugly origin, 英语词源]