'clear-voiced' originates from Modern English, formed by combining 'clear' (from Old English 'clǣre') and 'voice' (from Latin 'vox' via Old French 'voiz'), where 'clear' meant 'bright, free from obscurity' and 'voice' meant 'sound produced by the vocal organs'.

'clear' changed from Old English 'clǣre' to Middle and then Modern English 'clear'; 'voice' changed from Latin 'vox' to Old French 'voiz' and then to Middle English 'voice'. The compound 'clear-voiced' was formed in Modern English by combining these elements to describe the quality of a voice.

Initially components meant 'bright/clear' and 'sound of the voice' literally; over time the compound came to be used adjectivally to describe vocal quality and, by extension, clarity of expression.