'Aragon' originates from Spanish, specifically the word 'Aragón', ultimately taken from the name of the river 'Aragón'. The river-name's deeper origin is uncertain and may be pre-Roman or from local Basque-Iberian roots.

'Aragon' changed from the river-name 'Aragón' to refer to the Frankish/medieval County and then the 'Kingdom of Aragon' in the medieval period; that polity later became part of the Crown of Aragon and, in modern times, the name denotes the autonomous community.

Initially it meant the name of the river 'Aragón', but over time it evolved to mean the territory associated with that river (the medieval kingdom) and today refers to the modern region/autonomous community of northeastern Spain.