Precaution vs Preventing - What's the difference?

As a noun precaution

is precaution.

(en noun)

Previous caution or care; caution previously employed to prevent mischief or secure good; as, his life was saved by precaution.

* John Henry Newman

The ancient philosophers treasured up their supposed discoveries with miserable precaution .

A measure taken beforehand to ward off evil or secure good or success; a precautionary act.

to take precautions against risks of accident

* precautionary

(en verb)

(transitive): To warn or caution beforehand. --.

(rare): To take precaution against. --.

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