'post-anesthesia' originates from the prefix 'post-' meaning 'after' and 'anesthesia' from Greek 'anaisthēsia', where 'an-' meant 'without' and 'aisthēsis' meant 'sensation'.

'anaisthēsia' transformed into the modern English word 'anesthesia', and combined with 'post-' to form 'post-anesthesia'.

Initially, it meant 'after the loss of sensation', but over time it evolved into its current meaning of 'relating to the period following anesthesia'.