'constant' originates from Latin, specifically the word 'constans,' where 'con-' meant 'together' and 'stare' meant 'to stand.'

'constans' transformed into the Old French word 'constant,' and eventually became the modern English word 'constant' through Middle English.

Initially, it meant 'standing firm or steadfast,' but over time it evolved into its current meaning of 'unchanging or invariable.'