'rule-bound' originates from the combination of 'rule' and 'bound', where 'rule' refers to a set of explicit or understood regulations or principles, and 'bound' means restricted or confined.

'Rule-bound' evolved from the Middle English word 'bounden', which meant obligated or constrained, combined with 'rule'.

Initially, it meant 'confined by rules', and this meaning has largely remained the same in modern usage.