vowel (n.) Look up vowel at Dictionary.com
c.1300, from Old French voieul (Modern French voyelle), from Latin vocalis, in littera vocalis, literally "vocal letter," from vox (genitive vocis) "voice" (see voice (n.)). Vowel shift in reference to the pronunciation change between Middle and Modern English is attested from 1909. The Hawaiian word hooiaioia, meaning "certified," has the most consecutive vowels of any word in current human speech; the English record-holder is queueing.