Keep one article away from us (5)

I believe the answer is:

guard

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'keep' is the definition.
(I know that guard is a kind of defend)

I can't explain the rest of the clue.

(Other definitions for guard that I've seen before include "Sentinel" , "security man" , "state of caution" , "Sentry" , "Escort" .)

I've seen this clue in The Guardian.

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