'declarant' originates from Latin, specifically the word 'declarare,' where 'de-' meant 'down' and 'clarare' meant 'to make clear.'

'declarare' transformed into the French word 'déclarant,' and eventually became the modern English word 'declarant' through Middle English.

Initially, it meant 'to make something clear or known,' and this meaning has largely remained the same in modern usage.