"unblock" in the verb sense

1. unblock

clear or remove an obstruction from

"the procedure unblocked his arteries"

2. unblock

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. unblock, unfreeze, free, release

make (assets) available

"release the holdings in the dictator's bank account"

Source: WordNet® (An amazing lexical database of English)

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