LOCK, n. [L. floccus, Eng. lock.]

1. Lock, in its primary sense, is any thing that fastens; but we now appropriate the word to an instrument composed of a spring, wards, and a bolt of iron or steel, used to fasten doors, chests and the like. The bolt is moved by a key.
2. The part of a musket or fowling-piece or other fire-arm, which contains the pan, trigger, &c.
3. The barrier or works of a canal, which confine the water, consisting of a dam, banks or walls, with two gates or pairs of gates, which may be opened or shut at pleasure.
4. A grapple or wrestling. – Milton.
5. Any inclosure. – Dryden.
6. A tuft of hair; a plexus of wool, hay or other like substance; a flock; a ringlet of hair. A lock of hair will draw more than a cable rope. – Grew. Lock of water, is the measure equal to the contents of the chamber of the locks by which the consumption of water on a canal is estimated.

1. To become fast. The door locks close.
2. To unite closely by mutual insertion; as, they lock into each other. – Boyle.

1. To fasten with a particular instrument; as, to lock door; to lock a trunk.
2. To shut up or confine, as with a lock; as, to be locked in a prison; Lock the secret in your breast.
3. To close fast. The frost locks up our rivers.
4. To embrace closely; as, to lock one in the arms.
5. To furnish with locks, as a canal.
6. To confine; to restrain. Our shipping was locked up by the embargo.
7. In fencing, to seize the sword arm of an antagonist, by turning the left arm around it, after closing the parade, shell to shell, in order to disarm him. – Cyc.

1. A tuft of hair; a flock or small quantity of wool, hay, or other like substance; a tress or ringlet of hair.
   
   

   These gray locks, the pursuivants of death. Shak.

2. 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.
3. 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.
4. To become fast, as by means of a lock or by interlacing; as, the door locks close.
   
   

   When it locked none might through it pass. Spenser.

   To lock into, to fit or slide into; as, they lock into each other. Boyle.

5. A fastening together or interlacing; a closing of one thing upon another; a state of being fixed or immovable.
   
   

   Albemarle Street closed by a lock of carriages. De Quincey.

6. 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.
7. A place from which egress is prevented, as by a lock.
   
   
   Dryden.
8. 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.
9. The barrier or works which confine the water of a stream or canal.
10. To link together; to clasp closely; as, to lock arms.
    
    
    " Lock hand in hand." Shak.
11. 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.
12. To furnish with locks; also, to raise or lower (a boat) in a lock.
13. That part or apparatus of a firearm by which the charge is exploded; as, a matchlock, flintlock, percussion lock, etc.
14. To seize, as the sword arm of an antagonist, by turning the left arm around it, to disarm him.
15. A device for keeping a wheel from turning.
16. A grapple in wrestling.
    
    
    Milton.

    Detector lock, a lock containing a contrivance for showing whether it as has been tampered with. -- Lock bay (Canals), the body of water in a lock chamber. -- Lock chamber, the inclosed space between the gates of a canal lock. -- Lock nut. See Check nut, under Check. -- Lock plate, a plate to which the mechanism of a gunlock is attached. -- Lock rail (Arch.), in ordinary paneled doors, the rail nearest the lock. Lock rand (Masonry), a range of bond stone. Knight. -- Mortise lock, a door lock inserted in a mortise. -- Rim lock, a lock fastened to the face of a door, thus differing from a mortise lock.