Put up with someone hard to put up with (4)

I believe the answer is:

bore

'someone hard to put up with' is the definition.

I don't understand how the rest of the clue works.

(Other definitions for bore that I've seen before include "Capable of being shifted" , "Tedious thing" , "A tedious talkative person" , "Suffered" , "No fun" .)

I've seen this clue in The Guardian.

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