Open English Wordnet
Nouns
(n)knock, knockingthe sound of knocking (as on a door or in an engine or bearing)“the knocking grew louder” (n)knock, bash, bang, smash, belta vigorous blow“the sudden knock floored him”,
“he took a bash right in his face”,
“he got a bang on the head” (n)knocka bad experience“the school of hard knocks” Verbs
(v)knock, strike harddeliver a sharp blow or push“He knocked the glass clear across the room” (v)knockrap with the knuckles“knock on the door” (v)bump, knockknock against with force or violence“My car bumped into the tree” (v)tap, rap, knock, pinkmake light, repeated taps on a surface“he was tapping his fingers on the table impatiently” (v)pink, ping, knocksound like a car engine that is firing too early“the car pinged when I put in low-octane gasoline”,
“The car pinked when the ignition was too far retarded” (v)knock, criticize, criticise, pick apartfind fault with; express criticism of; point out real or perceived flaws“The paper criticized the new movie”,
“Don't knock the food — it's free”