'acronyctous' originates from Greek, specifically the word 'akronyktos,' where 'akro-' meant 'extreme' and 'nyktos' meant 'night.'

'akronyktos' transformed into the Latin word 'acronyctus,' and eventually became the modern English word 'acronyctous.'

Initially, it meant 'extreme night,' but over time it evolved into its current meaning of 'active during the night.'