what are the 2 dots above a u called
Diaeresis (diacritic) The diaeresis (/daɪˈɛrɪsɪs/ dy-ERR-ə-sis; plural: diaereses), also spelled diæresis or dieresis and also known as the tréma (also: trema) or the umlaut, is a diacritical mark that consists of two dots ( ¨ ) placed over a letter, usually a vowel. When that letter is an i or a j, the diacritic replaces the tittle: ï.[1]