UNBLOCK
unblock, unfreeze, free, release
(verb) make (assets) available; “release the holdings in the dictator’s bank account”
unblock
(verb) 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
unblock
(verb) clear or remove an obstruction from; “the procedure unblocked his arteries”
Source: WordNet® 3.1
Etymology
Verb
unblock (third-person singular simple present unblocks, present participle unblocking, simple past and past participle unblocked)
(transitive) To remove or clear a block or obstruction from.
Synonym: deobstruct
(transitive) To free or make available.
(intransitive, card games) In whist, to throw away a high card so as not to interrupt one's partner's long suit.
Source: Wiktionary