1.To obstruct so as to prevent passage or progress; to prevent passage from, through, or into, by obstructing the way; used both of persons and things; often followed by up; as, to block up a road or harbor; to block an entrance. "With moles... would block the port." "A city... besieged and blocked about."
2.To secure or support by means of blocks; to secure, as two boards at their angles of intersection, by pieces of wood glued to each.
3.To shape on, or stamp with, a block; as, to block a hat.
4.To cause (any activity) to halt by creating an obstruction; as, to block a nerve impulse; to block a biochemical reaction with a drug.
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