%blockade%

n. [ Cf. It. bloccata. See Block, v. t. ] 1. The shutting up of a place by troops or ships, with the purpose of preventing ingress or egress, or the reception of supplies; as, the blockade of the ports of an enemy. [ 1913 Webster ]

☞ Blockade is now usually applied to an investment with ships or vessels, while siege is used of an investment by land forces. To constitute a blockade, the investing power must be able to apply its force to every point of practicable access, so as to render it dangerous to attempt to enter; and there is no blockade of that port where its force can not be brought to bear. Kent. [ 1913 Webster ]

2. An obstruction to passage. [ 1913 Webster ]

3. (physiology) interference with transmission of a physiological signal, or a physiological reaction. [ PJC ]

To raise a blockade. See under Raise. [ 1913 Webster ]