'assagai' (variant spelling 'assegai') originates from Portuguese, specifically the word 'azagaia', meaning 'spear'.

'assagai' entered English via Portuguese 'azagaia' (also attested in 16th–17th century travel and colonial accounts) and through contact with southern African languages; the modern English forms 'assegai' and 'assagai' reflect these borrowings.

Initially it referred specifically to the portuguese/african light spear 'azagaia' (a throwing/stabbing spear); the core meaning has remained a type of spear, with occasional extension to the action of using such a spear ('to assagai').