Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “lock”

See all translations

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
More examples

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.
More examples

lock verb (BECOME FIXED)

[I] to become fixed in one position: I tried to start moving but the wheels had locked.
(Definition of lock from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of lock?
Add Cambridge dictionaries to your browser to your website

Definitions of “lock” in other dictionaries

Word of the Day

ice over

If an area of water ices over, it becomes covered with a layer of ice.

Word of the Day

Let’s celebrate! (words and phrases for parties)

by Kate Woodford,
December 17, 2014
​​​ With Christmas and New Year almost upon us, we thought it a good time to look at the language of parties and celebrations. First, let’s start with the word ‘party’ itself. To have or throw a party or, less commonly, to give a party is to arrange a party: We’re having a

Read More 

cinderella surgery noun

December 15, 2014
cosmetic surgery to the feet We have all heard of people having nose jobs, boob jobs and liposuction – but now a new trend growing in popularity in America: Cinderella surgery.

Read More