Linguistics 【语言学】
1
- a mark (··) used over a vowel, especially in German, to indicate a different vowel quality（德语中表示不同元音音质）曲音符号(··)。
1.1
- mass noun the process in Germanic languages by which the quality of a vowel was altered in certain phonetic contexts, resulting for example in the differences between modern German Mann and Männer（日耳曼语系）曲音变化。
词源
mid 19th cent.: from German Umlaut, from um 'about' + Laut 'sound'.