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English definition of “knock”

knock

verb uk   /nɒk/ us    /nɑːk/

knock verb (MAKE NOISE)

B1 [I] to repeatedly hit something, producing a noise: She knocked on the window to attract his attention. There's someone knocking on/at the door. Please knock before entering.Hitting against objects accidentally and colliding [I] specialized engineering If an engine is knocking, it is producing a repeated high sound either because the fuel is not burning correctly or because a small part is damaged and is therefore allowing another part to move in ways that it should not.Sounds made by objects, movement or impact [I] If something such as a pipe knocks, it makes a repeated high sound.Sounds made by objects, movement or impact

knock verb (HIT)

B1 [I + adv/prep, T] to hit, especially forcefully, and cause to move or fall: He accidentally knocked the vase off the table. She knocked her head against the wall as she fell. Who knocked over that mug of coffee? [+ obj + adj ] Some thug knocked him unconscious/senseless. She took a hammer and knocked a hole in the wall.Hitting against objects accidentally and colliding knock into each other/knock through If you knock two rooms into each other or knock two rooms through, you remove the wall between them so that they form one room.Connecting and combiningVariety and mixturesMixing and mixturesConstruction work and workers

knock verb (CRITICIZE)

[T] UK informal to criticize, especially unfairly: Don't knock him - he's doing his best.Disapproving and criticizingDamaging reputation

knock

noun [C] uk   /nɒk/ us    /nɑːk/

knock noun [C] (NOISE)

a sudden short noise made when someone or something hits a surface: There was a knock at/on the door.Sounds made by objects, movement or impact

knock noun [C] (HIT)

the act of something hard hitting a person or thing: He received a nasty knock on the head from a falling slate.Hitting against objects accidentally and colliding
(Definition of knock from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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