dieresis

[dahy-er-uh-sis] /daɪˈɛr ə sɪs/
noun, plural diereses
[dahy-er-uh-seez] /daɪˈɛr əˌsiz/ (Show IPA)
1.
the separation of two adjacent vowels, dividing one syllable into two.
2.
a sign (¨) placed over the second of two adjacent vowels to indicate separate pronunciation, as in one spelling of the older forms naïve and coöperate: no longer widely used in English.
3.
Prosody. the division made in a line or verse by coincidence of the end of a foot and the end of a word.
Also, diaeresis.
Origin
1605-15; < Latin diaeresis < Greek diaíresis literally, distinction, division, equivalent to diaire-, stem of diaireîn to divide (di- di-3 + haireîn to take) + -sis -sis
Related forms
dieretic
[dahy-uh-ret-ik] /ˌdaɪ əˈrɛt ɪk/ (Show IPA), adjective
Examples from the web for dieresis
  • Ketone-induced dieresis occurs, accompanied by loss of magnesium, phosphorus and calcium.
British Dictionary definitions for dieresis

diaeresis

/daɪˈɛrɪsɪs/
noun (pl) -ses (-ˌsiːz)
1.
the mark ¨, in writing placed over the second of two adjacent vowels to indicate that it is to be pronounced separately rather than forming a diphthong with the first, as in some spellings of coöperate, naïve, etc
2.
this mark used for any other purpose, such as to indicate that a special pronunciation is appropriate to a particular vowel Compare umlaut
3.
a pause in a line of verse occurring when the end of a foot coincides with the end of a word
Derived Forms
diaeretic, dieretic (ˌdaɪəˈrɛtɪk) adjective
Word Origin
C17: from Latin diarēsis, from Greek diairesis a division, from diairein, from dia- + hairein to take; compare heresy

dieresis

/daɪˈɛrɪsɪs/
noun (pl) -ses (-ˌsiːz)
1.
a variant spelling of diaeresis
Derived Forms
dieretic (ˌdaɪəˈrɛtɪk) adjective
Word Origin and History for dieresis
n.

also diaeresis, 1610s, "sign marking the division of a diphthong into two simple sounds," from Late Latin diaeresis, from Greek diairesis "division," noun of action from diairein "to divide, separate," from dia- "apart" (see dia-) + hairein "to take" (see heresy).

dieresis in Medicine

dieresis di·er·e·sis (dī-ěr'ĭ-sĭs)
n.
See solution of continuity.

Encyclopedia Article for dieresis

diaeresis

(from Greek diairein, "to divide"), the resolution of one syllable into two, especially by separating the vowel elements of a diphthong and, by extension, two adjacent vowels, as in the word cooperation; it is also the mark placed over a vowel to indicate that it is pronounced as a separate syllable. In classical prosody, diaeresis refers to the end of a word coinciding with the completion of the metrical foot, in contrast to caesura, which refers to a word ending within a metrical foot

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