'affectlessness' originates from the English word 'affectless,' where 'affect' meant 'emotion or feeling' and the suffix '-less' indicates 'without.'

'affectless' changed from the Middle English word 'affect' and eventually became the modern English word 'affectless' with the addition of the suffix '-less.'

Initially, it meant 'without emotion or feeling,' and this meaning has largely remained the same in modern usage.