'weapon-free' is a compound word formed from 'weapon' and 'free', where 'weapon' refers to an instrument used for attack or defense, and 'free' means not having or being subject to something.

'Weapon' comes from Old English 'wǣpen', and 'free' comes from Old English 'frēo'. The combination of these words into 'weapon-free' is a modern English formation.

Initially, 'weapon' referred to any tool used for fighting, and 'free' meant not constrained. Together, 'weapon-free' evolved to mean not carrying or using weapons.