dieresis

noun6

1. •
   The diacritical mark consisting of two dots (¨) placed over a letter (especially the second of two consecutive vowels) to indicate that it is sounded separately, usually as a distinct syllable.

   • Diaeresis is vvhen tvvo points ouer a vovvell diuide it from another vovvel, as bouë, queuë, read bou-e, queu-e, not bo-ue, que-ue. — 1611
2. •
   A separation of one syllable (especially a vowel which is a diphthong, that is, beginning with one sound and ending with another) into two distinct syllables; distraction.
3. •
   An occurrence of separate vowel sounds in adjacent syllables without an intervening consonant; a hiatus.
4. •
   A natural break in rhythm when a word ends at the end of a metrical foot in a line of verse.
5. •
   (figurative, rare) A division, a separation.
6. •
   (no longer used) An act of separating body parts or tissues which are normally together.

   • There are four^([sic]) manners of performing the Diaeresis: viz. by Cutting, Pricking, Tearing, Dravving, and Burning. — 1728