Blockade (&unr_;), 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.
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&hand_; 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.
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2. An obstruction to passage.
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3. (physiology) interference with transmission of a physiological signal, or a physiological reaction.
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To raise a blockade. See under Raise.
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