diaeresis or dieresis
📖 Definitions
noun
1. The separation of two adjacent vowel sounds.
2. The mark ¨ placed over a vowel to indicate that it’s pronounced as a separate syllable, for example, in naïve or Brontë.
3. A break in a line of verse when the end of a word coincides with the end of the metric foot.
💬 Usage Examples
“However, it was not until much later in life that Patrick went a step further and adopted the diaeresis which was to make the name Brontë.” James Tully; The Crimes of Charlotte Brontë; Constable & Robinson; 1999.