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1. Clear or remove an obstruction from
   "the procedure unblocked his arteries"
    
2. Play the cards of (a suit) so that the last trick on which a hand can follow suit will be taken by a higher card in the hand of a partner who has the remaining cards of a combined holding
    
3. Make (assets) available
   "unblock the holdings in the dictator's bank account"
   - unfreeze, free, release

Derived forms: unblocked, unblocking, unblocks

Type of: issue, loosen up, play, supply, unstuff

Antonym: block