part of speech: verb

inflections: knocks, knocking, knocked

definition 1: to rap, pound, or hit something, such as a door.

  • Please knock before you enter the room.

synonyms: drum, tap

definition 2: to bump or crash.

  • Eric’s bumper car knocked into mine.

synonyms: bump, jar

definition 3: to make a pounding or beating sound.

  • The car’s engine knocks.

synonyms: thump

definition 4: to give a sharp blow to; strike; hit.

  • The boxers knocked each other in the head several times.

synonyms: hit, rap, smack, strike


part of speech: noun

definition 1: the act or an instance of knocking.

  • A knock on the door woke me up.

synonyms: rap, tap

definition 2: a sound made by a bad engine.

  • When did you first hear the knock in your car?