'effortless' originates from the word 'effort' combined with the suffix '-less', where 'effort' meant 'exertion of physical or mental energy' and '-less' meant 'without'.

'effort' changed from the Old French word 'esforz' and eventually became the modern English word 'effort'.

Initially, it meant 'without exertion of energy', and this meaning has largely remained the same in modern usage.