dieresis

noun
  1. A mark (¨) placed over a vowel to indicate that it is pronounced separately from an adjacent vowel, as in the word 'naïve'.
  2. Usage: Also called a diaeresis in some contexts.; Common in English borrowed from French and other languages.
  3. In poetry and classical meter, the coincidence of a metrical division with a word boundary.
  4. Usage: Technical term used in prosody and literary analysis.; Rare in modern usage.

Examples