An alternative or archaic form meaning voiceless or unable to produce sound, similar to aphonic.
From Greek 'a-' (without) + 'phōnē' (voice) with the suffix '-ous' (full of, characterized by); an older English variant of aphonic.
This older word form shows how English medical terminology has evolved—aphonous is rarely used now because aphonic became the standard, but both come from the same Greek roots.
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