Overview
The diaeresis is a diacritical mark formed by two dots placed above a vowel. In orthographic use, it signals that adjacent vowels should be read separately rather than combined as a diphthong or a single phonetic unit.
In modern English it appears rarely, mostly in traditional editorial spellings such as naïve, coöperate, and Noël.
Representative Usage
Examples traditionally cited in English-language typography include:
- naïve
- coöperate
- Noël
- reëlect
Greek tradition
Used to mark vowel separation in manuscript practice and learned reading traditions.
Editorial style
Retained in formal publishing for clarity or historical continuity.
Orthographic Context
In historical orthography, the diaeresis plays a clarifying role. When two vowels appear side by side in a word, readers may naturally interpret them as forming a single sound or diphthong. The diaeresis prevents this interpretation and signals that the vowels belong to separate syllables.
For example, in the traditional spelling coöperate, the diaeresis indicates that the word should be pronounced as co-operate rather than coop-erate. Similar usage appears in words such as naïve and Noël.
Although the mark has largely disappeared from everyday English spelling, it remains historically significant and is still preserved in dictionaries, academic writing, and certain editorial traditions.