'dispensary' originates from Medieval Latin/Latin, specifically the word 'dispensarium' from Latin 'dispensare' meaning 'to distribute', where 'dis-' meant 'apart' and the root related to 'weigh/measure' or 'hand out'.

'dispensary' passed into Middle English from Old French/Medieval Latin forms such as 'dispensaire'/'dispensarium' and eventually became the modern English 'dispensary'.

Initially it meant 'a place for distribution' in a general sense, and over time it narrowed to mean specifically places that dispense medicines or medical supplies (and more recently retail outlets dispensing cannabis in jurisdictions where that is legal).