umlaut
n
(a) [U] (in Germanic languages) vowel change in related forms of a word, shown by two dots over the vowel in one of them, eg der Mann/die Manner (= the man/the men) in German (日耳曼语系中的)元音变化(在元音上加两点作为标志, 如德语中的 der Mann/die Manner).
(b) [C] sign (consistingof two dots) that shows this 变音符(标示上述元音变化的两点). Cf 参看 diaeresis.