'accidia' originates from Latin, specifically the word 'acedia,' where 'a-' meant 'without' and 'kedos' meant 'care.'

'acedia' transformed into the Medieval Latin word 'accidia,' and eventually became the modern English word 'accidia.'

Initially, it meant 'without care or concern,' but over time it evolved into its current meaning of 'spiritual or mental sloth.'