to hit a door to get someone's attention
Please knock before entering the room.
to hit something hard by accident
I didn't mean to knock the cup off the table.
to hit something to move or break it
The children knock the ball back and forth.
to hit someone or something into a state
The punch will knock him out cold.
to make a hole by hitting hard
They had to knock a hole in the wall for the pipe.
to beat hard or shake from fear
My heart began to knock when I heard the noise.
to make a regular metal hitting sound
The old engine began to knock loudly.
to criticize unfairly
Some people always knock new ideas without trying them.
the sound of hitting a door to get attention
I heard a loud knock at the door.
a hard hit from something
The knock on his head made him dizzy.
a bad experience that reduces confidence
Losing the game was a real knock to his pride.