Hey you! Yes, you! Thank you for adding beauty to the world!
Definitions of diaresis:
noun: Alternative spelling of diaeresis [(orthography) A diacritic ( ¨ ) placed over a vowel letter (especially the second of two consecutive ones) indicating that it is sounded separately, usually forming a distinct syllable, as in the English words naïve, Noël and Brontë, the French haïr and the Dutch ruïne.]