'agnosia' originates from Greek, specifically the word 'agnōsia,' where 'a-' meant 'without' and 'gnōsis' meant 'knowledge.'

'agnōsia' transformed into the Latin word 'agnosia,' and eventually became the modern English word 'agnosia' through Middle English.

Initially, it meant 'lack of knowledge,' but over time it evolved into its current meaning of 'inability to recognize objects, persons, or sounds.'