What is "dieresis"

Dieresis \Di*er"e*sis\, n. [NL.] Same as Di[ae]resis.

Diaeresis \Di*[ae]r"e*sis\, Dieresis \Di*er"e*sis\ (?; 277), n.; pl. Di[ae]reses or Diereses. [L. diaeresis, Gr. ?, fr. ? to divide; dia` through, asunder + ? to take. See Heresy.]

1. (Gram.) The separation or resolution of one syllable into two; -- the opposite of syn[ae]resis.

2. A mark consisting of two dots [[umlaut]], placed over the second of two adjacent vowels, to denote that they are to be pronounced as distinct letters; as, co["o]perate, a["e]rial.

also diaeresis, 1610s, "sign marking the division of a diphthong into two simple sounds," from Late Latin diaeresis, from Greek diairesis "division," noun of action from diairein "to divide, separate," from dia- "apart" (see dia-) + hairein "to take" (see heresy). In classical prosody, "the slight break in the forward motion of a line that is felt when the end of a foot coincides with the end of a word" [Miller Williams, "Patterns of Poetry"].

n. (alternative form of diaeresis English)

1. n. a diacritical mark (two dots) placed over a vowel in German to indicate a change in sound [syn: umlaut, diaeresis]

2. [also: diereses (pl)]