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English definition of “lock”

lock

noun uk   /lɒk/ us    /lɑːk/

lock noun (FASTENER)

B1 [C] a device that prevents something such as a door from being opened and can only be opened with a key: I heard someone turn a key in the lock. safety locks Thieves got in by smashing the lock off the door.
See also

lock noun (WATER)

[C] a length of water with gates at each end where the level of water can be changed to allow boats to move between parts of a canal or river that are at different heights

lock noun (DEFINITE EVENT)

[C] US informal something that is certain to happen: She's a lock for promotion this year.

lock noun (HAIR)

[C] a small group of hairs, especially a curl: There is a lock of Napoleon's hair in the display cabinet. locks [plural] literary the hair on someone's head: curly locks flowing golden locks

lock noun (WHEELS)

[U] UK the amount a road vehicle's front wheels can be turned from one side to the other by turning its steering wheel: You need it on full lock (= with the wheel turned as much as possible).

lock noun (HOLD)

[C] a way of holding someone that you are fighting against so that they cannot move: The smaller wrestler held his opponent in a full body lock.

lock

verb uk   /lɒk/ us    /lɑːk/

lock verb (MAKE SAFE)

B2 [T usually + adv/prep] to put something in a safe place and fasten the lock: He locked the confidential documents in his filing cabinet. You really should lock your car (up) or it'll get stolen. B1 [I or T] to fasten something with a key, or be fastened with a key: Don't forget to lock the door when you go out. If you shut the door it will lock automatically.

lock verb (BECOME FIXED)

[I] to become fixed in one position: I tried to move forwards but the wheels had locked.
(Definition of lock from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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