Umlaut (diacritic)

The umlaut mark (or simply umlaut) and the diaeresis mark (or simply diaeresis) or trema are two diacritics consisting of a pair of dots placed over a letter. When the vowel is an i, the diacritic replaces the tittle. The two diacritics are very similar in appearance, and the distinction between them is not always made.
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