'achronical' originates from Greek, specifically the word 'akhronikos,' where 'a-' meant 'not' and 'khronos' meant 'time.'

'akhronikos' transformed into the Latin word 'achronicus,' and eventually became the modern English word 'achronical.'

Initially, it meant 'not related to time,' but over time it evolved into its current meaning of 'occurring at nightfall.'