'loudness' originates from Old English, specifically the word 'hlūdness,' where 'hlūd' meant 'loud' and '-ness' was a suffix indicating a state or quality.

'hlūdness' transformed into the Middle English word 'loudnesse,' and eventually became the modern English word 'loudness'.

Initially, it meant 'the state of being loud,' and this meaning has largely remained the same in modern usage.