Definition of "vowel" []

• A speech sound, such as (ē) or (ĭ), created by the relatively free passage of breath through the larynx and oral cavity, usually forming the most prominent and central sound of a syllable. (noun)
• A letter, such as a, e, i, o, u, and sometimes y in the English alphabet, that represents a vowel. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "If the voice thus produced comes out through the mouth held well open, a class of sounds is formed which we call vowel sounds."
• "Meanwhile the eh vowel is moving towards the short-u uh vowel so that ‘bed’ is starting to sound like ‘bud’."
• "One of the main reason why you must NOT make a liaison after "et" (= 'and', pronounced "é") in front of a vowel is often to avoid nonsense and confusion."