Pronunciation: (dī-er'u-sis), [key]
—pl. -sesPronunciation: (-sēz"). [key]
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. Pros.the division made in a line or verse by coincidence of the end of a foot and the end of a word. Also,diaeresis.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.