What does diaeresis mean?
Diaeresis refers to a small but purposeful typographic device: two dots placed over the second of two adjacent vowels to signal that they are pronounced separately rather than blended together, as in the borrowed French word 'naïve'. Without the mark, readers might naturally merge the vowels into one sound, so the diaeresis acts as a silent guide to correct pronunciation. The word also carries an older, technical meaning in classical prosody, where it denotes the pause or break between metrical feet that coincides with a word boundary in verse. Derived from Greek roots meaning 'to divide through', diaeresis belongs to the vocabulary of typography, linguistics, and literary scholarship rather than everyday speech. It is most familiar to careful editors, translators, and students of poetry, and it remains useful precisely because English so rarely marks such distinctions explicitly.
nounThe division of two adjacent vowels that would normally form a diphthong or be pronounced together, marked in English by a diaeresis sign (¨) over the second vowel, as in naïve or Chloë. In prosody, it is also the break or pause between the feet of a line of verse occurring at a word boundary.
- A diacritical mark consisting of two dots placed over the second of two adjacent vowels to show they are pronounced separately, as in 'naïve'.
- In prosody, the division or pause between metrical feet at a word boundary within a line of verse.
- Linguistically, the pronunciation of two adjacent vowels as separate sounds rather than as a diphthong.
"In 'naïve', the diaeresis signals that the 'a' and 'i' must be pronounced separately."
"Careful typesetters still use a diaeresis in words like 'coöperate' to prevent readers from pronouncing 'oo' as a single vowel."
"The critic noted that the diaeresis after the fourth foot gave the hexameter line an unusually deliberate pace."
The plural follows the Greek pattern with '-es', pronounced /daɪˈɛrəsiːz/. The American variant spelling yields 'diereses'.
"Older British texts are full of diaereses that modern typography has quietly abandoned."
That little pair of dots in 'naïve' has a proper name — diaeresis — and it exists purely to stop your eyes from gluing two vowels together.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of diaeresis
Diaeresis comes from the Greek noun 'diairesis', meaning 'division' or 'separation', formed from 'diairein', 'to divide', itself built on 'dia-' ('through') and 'hairein' ('to take'). It entered English in the early 17th century via Latin, initially in grammatical and rhetorical contexts before narrowing toward its modern typographic sense. It shares its Greek root with words such as 'heresy', 'analysis', and 'paralysis', all of which involve notions of taking apart or choosing among elements.
Usage notes
The spelling 'dieresis' (without the first 'e') is common in American English; both spellings are accepted. The plural is irregular: diaereses. The word is formal and largely confined to typography, linguistics, and classical prosody. The same symbol is often loosely called an umlaut, though the two serve different functions.
Don't confuse with
An umlaut signals a change in vowel sound (as in German), while a diaeresis merely indicates that two adjacent vowels are pronounced separately.