'precautionary' originates from the Latin word 'praecautio,' where 'prae-' meant 'before' and 'cautio' meant 'caution.'

'praecautio' transformed into the French word 'précaution,' and eventually became the modern English word 'precautionary' through Middle English.

Initially, it meant 'taking care beforehand,' and this meaning has largely remained the same in modern usage.