Translation guide
The act of striking a surface to make a sound, typically to gain entry or attention. In Japanese, the expression depends on the context: knocking on a door, a knocking sound, or metaphorical 'knocking' like criticism.
knock on the door
To strike a door with knuckles to request entry or announce presence.
The most common and neutral way to say 'knock on a door'. Borrowed from English, used in everyday situations.
Please knock on the door.
Someone is knocking.
Literally 'to hit/strike the door'. Can imply knocking, but also a harder hit. Use ノックする for polite knocking.
Can sound more forceful than a polite knock. ノックする is safer for everyday use.
He knocked hard on the door.
Onomatopoeic expression mimicking the sound of knocking. Often used in narratives or children's language.
He knocked knock-knock on the door.
The sound produced by knocking, often heard but source unknown.
The sound of knocking. ノック (knock) + 音 (sound).
I heard a knocking sound.
Generic 'hitting sound', can be knocking or other impacts.
There was a knocking sound on the wall.
Onomatopoeic description of a light knocking sound.
There was a knock-knock sound from the door.
To criticize or find fault with someone or something, often unfairly.
General term for 'criticize'. Not specific to 'knocking', but conveys the meaning of finding fault.
He's always knocking my work.
To speak ill of, disparage. Stronger than 批判する, closer to 'badmouth'.
To harshly criticize, tear down. Very strong, often used in reviews or arguments.
A metallic knocking sound from an engine, indicating a mechanical problem.
ノックする specifically means a polite knock to announce presence, while 叩く is a general verb for hitting or striking. Use ノックする when visiting someone's home or office.
Please knock before entering the room.
I heard a knocking at the door.
Stop knocking my ideas.
She's always knocking other people.
The critics knocked the movie.