'apartment' originates from French, specifically the word 'appartement', ultimately from Italian 'appartamento', where 'appartare' meant 'to separate'.

'apartment' changed from the Italian word 'appartamento' and the French 'appartement' and entered modern English as 'apartment' in the 17th century.

Initially, it meant 'a separated or partitioned space', but over time it evolved into its current meaning of 'a set of rooms forming a separate residence within a building'.