I must replace what’s at heart of bad offer (3)

I believe the answer is:

bid

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'offer' is the definition.
(synonyms)

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

(Other definitions for bid that I've seen before include "Offer a sum of money to buy" , "Offer; command" , "Attempt, offer" , "Offer (for); demand" , "Make an offer at auction" .)

I've seen this clue in The Times.

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