Umlaut

The word umlaut is used in both linguistic and typographic senses.

Linguistics

In linguistics, the term umlaut is used in a variety of closely related ways, some narrower, some broader:

• Germanic umlaut — in its original, narrowest sense, the fronting of vowels in a Germanic language, caused by assimilation to an original front vowel in the following syllable, especially viewed diachronically.
• I-mutation — the above phenomenon in any language, sometimes called umlaut. A less controversial term is "i-mutation".
  • Affection (linguistics) — an example of this in another language family is the parallel phenomenon in Celtic languages.
• Vowel harmony and metaphony — more broadly still, sometimes umlaut refers to any example of metaphony, or "regressive vowel harmony".
  • A-mutation (an example of the above) — the velarisation of vowels caused by an original back vowel in a following syllable, which is occasionally called a-umlaut.
• Apophony - viewed synchronically, umlaut is an example of apophony or vowel alternation, and is occasionally used erroneously as a synonym.
  • Indo-European ablaut - in particular, umlaut is often confused with ablaut.

Orthography

• Umlaut (diacritic). In orthography, the term umlaut is sometimes used as a shortening of "umlaut mark", a diacritic. It is used in German spelling to represent the synchronic results of Germanic phonological Umlaut, and subsequently in other languages which borrowed the symbol. The symbol appears as a pair of dots above a vowel, such as <ä> in "Doppelgänger". It has the same appearance as a diaeresis, such as <ö> in "Coöperate".
  • Heavy metal umlaut - the umlaut diacritic has been used for sensational spellings in the rock music scene.