'anaesthetize' originates from Greek, specifically the word 'anaisthēsia,' where 'an-' meant 'without' and 'aisthēsis' meant 'sensation.'

'anaisthēsia' was adopted into modern English as 'anaesthesia,' and the verb form 'anaesthetize' was later formed to mean 'to make insensible.'

Initially, it meant 'to make insensible or without feeling,' and over time it evolved into its current medical meaning of 'to administer an anaesthetic.'