1. 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.
2. A letter, such as a, e, i, o, u, and sometimes y in the English alphabet, that represents a vowel.
[Middle English vowelle, from Old French vouel, from Latin (littera) vōcālis, sounding (letter), from vōx, vōc-, voice; see wekw- in the Appendix of Indo-European roots.]
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