'argan' originates from Berber (Amazigh), specifically the word 'argan', where it referred to the tree and its fruit.

'argan' passed into European languages (via Moroccan Arabic and then French, e.g. French 'arganier') and was adopted into English from these sources, yielding the modern English 'argan'.

Initially it referred specifically to the tree and its fruit; over time the term also came to be associated with the oil extracted from the fruit (argan oil), so its usage broadened to include both the plant and its product.