monophthong

phonetics

Also known as: pure vowel

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June 30, 2026

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A monophthong is a vowel sound that remains constant throughout its articulation. This means the tongue and lips do not change position while the sound is being produced. Monophthongs are contrasted with diphthongs, which are gliding vowel sounds where the articulation moves from one position to another. For example, the vowel sound in "cat" is a monophthong, while the vowel sound in "ice" is a diphthong. Phonetics is the study of speech sounds, and monophthongs are a fundamental category within this field.12345

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vowel
…with so-called pure vowels, or monophthongs—i.e., unchanging, or steady-state, vowels. Though they are single speech sounds, diphthongs are usually represented, in a phonetic transcription of speech, by means of a pair of characters indicating the initial and final configurations of the vocal tract. Many of the vowel sounds in most…
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…with so-called pure vowels, or monophthongs—i.e., unchanging, or steady-state, vowels. Though they are single speech sounds, diphthongs are usually represented, in a phonetic transcription of speech, by means of a pair of characters indicating the initial and final configurations of the vocal tract. Many of the vowel sounds in most…
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