'after-hours' originates from the combination of 'after' and 'hours', where 'after' meant 'following in time' and 'hours' referred to 'a fixed period of time'.

'after-hours' evolved from the phrase 'after the hours of business' to its current form, emphasizing activities occurring beyond regular business hours.

Initially, it referred to any time following a specific period, but over time it evolved to specifically denote activities occurring beyond regular business hours.