'congressman' originates from the English word 'congress,' which comes from the Latin 'congressus,' meaning 'a meeting or assembly.'

'congressus' transformed into the Old French word 'congres,' and eventually became the modern English word 'congress' with the addition of 'man' to denote a male member.

Initially, it meant 'a member of a meeting or assembly,' but over time it evolved into its current meaning of 'a member of the US House of Representatives.'