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1. Not forming a syllable or the nucleus of a syllable; consisting of a consonant sound accompanied in the same syllable by a vowel sound or consisting of a vowel sound dominated by other vowel sounds in a syllable (as the second vowel in a falling diphthong)
   "the nonsyllabic 'i' in 'oi'";
   - unsyllabic
    
2. (of speech sounds) not forming or capable of forming the nucleus of a syllable
   "initial 'l' in 'little' is nonsyllabic"

See also: unsyllabled

Antonym: syllabic

Encyclopedia: Nonsyllabic