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English definition of “lock”

lock

noun [C]  /lɑk/ us  

lock noun [C] (DEVICE TO FASTEN)

a device that keeps something, such as a door or drawer, fastened, usually needing a key to open it

lock noun [C] (WATER)

a length of water with gates at either 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 [C] (HAIR)

a curl of hair, or a group of hairs

lock

verb [I/T]  /lɑk/ us  

lock verb [I/T] (NOT ALLOW CHANGE)

to be or hold something in a position or condition where movement, escape, or change is not possible: [T] They’re locked in a lawsuit with their former employer. [I] The cars crashed and the bumpers locked, making it impossible to move. [M] The bank won’t lock in our mortgage rate.

lock verb [I/T] (FASTEN)

If you lock something somewhere, you make it safe by putting it in a special place and fastening it closed with a lock: [T] He locked the documents in his filing cabinet.
(Definition of lock from the Cambridge Academic Content Dictionary © Cambridge University Press)
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