Definition of lock

• n. - A tuft of hair; a flock or small quantity of wool, hay, or other like substance; a tress or ringlet of hair.
• n. - Anything that fastens; specifically, a fastening, as for a door, a lid, a trunk, a drawer, and the like, in which a bolt is moved by a key so as to hold or to release the thing fastened.
• n. - A fastening together or interlacing; a closing of one thing upon another; a state of being fixed or immovable.
• n. - A place from which egress is prevented, as by a lock.
• n. - The barrier or works which confine the water of a stream or canal.
• n. - An inclosure in a canal with gates at each end, used in raising or lowering boats as they pass from one level to another; -- called also lift lock.
• n. - That part or apparatus of a firearm by which the charge is exploded; as, a matchlock, flintlock, percussion lock, etc.
• n. - A device for keeping a wheel from turning.
• n. - A grapple in wrestling.
• v. t. - To fasten with a lock, or as with a lock; to make fast; to prevent free movement of; as, to lock a door, a carriage wheel, a river, etc.
• v. t. - To prevent ingress or access to, or exit from, by fastening the lock or locks of; -- often with up; as, to lock or lock up, a house, jail, room, trunk. etc.
• v. t. - To fasten in or out, or to make secure by means of, or as with, locks; to confine, or to shut in or out -- often with up; as, to lock one's self in a room; to lock up the prisoners; to lock up one's silver; to lock intruders out of the house; to lock money into a vault; to lock a child in one's arms; to lock a secret in one's breast.
• v. t. - To link together; to clasp closely; as, to lock arms.
• v. t. - To furnish with locks; also, to raise or lower (a boat) in a lock.
• v. t. - To seize, as the sword arm of an antagonist, by turning the left arm around it, to disarm him.
• v. i. - To become fast, as by means of a lock or by interlacing; as, the door locks close.