[f. as prec. + -ANCY.] The quality of being sonant.

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1875.  Whitney, Life Lang., iv. 59. A column of air emitted by the lungs, impressed with sonancy and variety of pitch by the larynx.

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1884.  Amer. Ann. Deaf & Dumb, Oct., 249. The sonants ‘soft’ or ‘flat,’ or ‘weak,’ especially when the element of sonancy is suppressed.

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