'agrypnia' originates from Greek, specifically the word 'ἀγρυπνία' (agrypnia), where 'ἀ-' meant 'not' and 'ὕπνος' (hypnos) meant 'sleep'.

The Greek word 'ἀγρυπνία' was adopted into Latin as 'agrypnia', and eventually became the modern English word 'agrypnia'.

Initially, it meant 'a state of being awake', but over time it evolved into its current meaning of 'a condition of sleeplessness or insomnia'.