Synonym: clasp, close, fasten, hook, latch, seal, shut. Antonym: unlock. Similar words: block, o'clock, local, locate, location, dock, sock, shock. Meaning: [lɑk /lɒk] 
n. 1. a fastener fitted to a door or drawer to keep it firmly closed 2. a strand or cluster of hair 3. a mechanism that detonates the charge of a gun 4. enclosure consisting of a section of canal that can be closed to control the water level; used to raise or lower vessels that pass through it 5. a restraint incorporated into the ignition switch to prevent the use of a vehicle by persons who do not have the key 6. any wrestling hold in which some part of the opponent's body is twisted or pressured. v. 1. fasten with a lock 2. keep engaged 3. become rigid or immoveable 4. hold in a locking position 5. become engaged or intermeshed with one another 6. hold fast (in a certain state) 7. place in a place where something cannot be removed or someone cannot escape 8. pass by means through a lock in a waterway 9. build locks in order to facilitate the navigation of vessels.
n. 1. a fastener fitted to a door or drawer to keep it firmly closed 2. a strand or cluster of hair 3. a mechanism that detonates the charge of a gun 4. enclosure consisting of a section of canal that can be closed to control the water level; used to raise or lower vessels that pass through it 5. a restraint incorporated into the ignition switch to prevent the use of a vehicle by persons who do not have the key 6. any wrestling hold in which some part of the opponent's body is twisted or pressured. v. 1. fasten with a lock 2. keep engaged 3. become rigid or immoveable 4. hold in a locking position 5. become engaged or intermeshed with one another 6. hold fast (in a certain state) 7. place in a place where something cannot be removed or someone cannot escape 8. pass by means through a lock in a waterway 9. build locks in order to facilitate the navigation of vessels. 
Random good picture Not show
1. Lock the stable door before the steed is stolen. 
2. It is too late to lock the stable door when the steed is stolen.
3. When the horse is stolen, (you) lock the stable door.
4. It is too late to lock the stable door when the horse is stolen.
5. Insert the key in/into the lock.
6. This suitcase won't lock because it is too full.
7. Push the tiny lever on the lock.
8. Don't forget to lock the door when you leave.
9. They shot the lock off .
10. I forgot to lock the door.
11. Someone has been tampering with the lock.
12. Don't forget to lock the door behind you .
13. Always lock your car whenever you leave it.
14. Lock up all the doors before you go out.
15. Did you lock the door?
15. Sentencedict.com is a sentence dictionary, on which you can find excellent sentences for a large number of words.
16. Will you lock up the house, please?
17. He turned the key in the lock.
18. I fumbled with the lock.
19. Always lock your bicycle to something secure.
20. She got the key stuck in the lock.
21. Please lock up these confidential reports.
22. It was sensible of you to lock the door.
23. She turned the key in the lock.
24. They pew their churches and sometimes lock them.
25. I heard someone turn a key in the lock.
26. The key doesn't fit the lock.
27. Did you lock the car?
28. Don't forget to lock the back door.
29. Would you be so kind as to lock the door when you leave?
30. A certain person, who shall remain nameless[sentencedict.com], forgot to lock the front door.