blockade

v. besiege, block, obstruct

n. siege, barrier, closure by sea

A blockade is any effort to prevent supplies, troops, information or aid from reaching an opposing force. Blockades are the cornerstone to nearly all military campaigns and the tool of choice for economic warfare on an opposing nation. The International Criminal Court plans to include blockades against coasts and ports in its list of acts of war in 2009.
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Noun
1. a war measure that isolates some area of importance to the enemy
(synonym) encirclement
(hypernym) military action, action
(hyponym) naval blockade
(derivation) seal off
(classification) military, armed forces, armed services, military machine, war machine
2. prevents access or progress
(hypernym) obstruction, obstructor, obstructer, impediment, impedimenta
(derivation) barricade, block, stop, block off, block up, bar
Verb
1. hinder or prevent the progress or accomplishment of; "His brother blocked him at every turn"
(synonym) obstruct, block, hinder, stymie, stymy, embarrass
(hypernym) prevent, forestall, foreclose, preclude, forbid
(hyponym) stonewall
2. render unsuitable for passage; "block the way"; "barricade the streets"; "stop the busy road"
(synonym) barricade, block, stop, block off, block up, bar
(hypernym) obstruct, obturate, impede, occlude, jam, block, close up
(hyponym) shut off, block off, close off
(verb-group) obstruct, block
3. obstruct access to
(synonym) block off
(hypernym) obstruct, obturate, impede, occlude, jam, block, close up
4. impose a blockade on
(synonym) seal off
(hypernym) besiege, beleaguer, surround, hem in, circumvent
(derivation) encirclement

n. blockade, siege, barrier

(v. t.)
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.
  

(v. t.)
An obstruction to passage.
  

(v. t. )
To shut up, as a town or fortress, by investing it with troops or vessels or war for the purpose of preventing ingress or egress, or the introduction of supplies. See note under Blockade, n.
  

(n.)
To obstruct entrance to or egress from.
  

(n.)
Hence, to shut in so as to prevent egress.