Unblock

v. [UN-² 3.]

  1.  trans. To free from an obstruction; to open up, to clear. Also fig.

1611.  Cotgr., Desblouquer, to vnblocke, or open the (blockt-vp) passages of.

1656.  Baxter, Reformed Pastor, 193. Our credit may do much to remove prejudice, and to unblock the entrance into mens minds.

  2.  Cards. To give free scope to (a partner’s suit) by playing an unnecessarily high card. Also absol.

1885.  ‘Cavendish,’ Whist Developments, Pref. p. x. The cases where the leader’s partner, when he does not head the trick, should play to unblock by retaining his lowest card (playing a higher one).

1899.  Melrose, Solo Whist, 12. This principle is known in whist as ‘unblocking’ partner’s suit.

  Hence Unblocking vbl. sb.

1885.  ‘Cavendish,’ Whist Developments, Pref. p. x. Hitherto it has been left to the ingenuity of individuals … to decide when and how the unblocking should be done.