Synonym: bang, beat, hammer, hit, jab, pound, punch, rap, strike. Similar words: knock out, knock off, knock down, know, on occasion, sock, dock, know about. Meaning: [nɑk /nɒk] 
n. 1. the sound of knocking (as on a door or in an engine or bearing) 2. negative criticism 3. a vigorous blow 4. a bad experience 5. the act of hitting vigorously. v. 1. deliver a sharp blow or push :"He knocked the glass clear across the room" 2. rap with the knuckles 3. knock against with force or violence 4. make light, repeated taps on a surface 5. sound like a car engine that is firing too early 6. find fault with; express criticism of; point out real or perceived flaws.
n. 1. the sound of knocking (as on a door or in an engine or bearing) 2. negative criticism 3. a vigorous blow 4. a bad experience 5. the act of hitting vigorously. v. 1. deliver a sharp blow or push :"He knocked the glass clear across the room" 2. rap with the knuckles 3. knock against with force or violence 4. make light, repeated taps on a surface 5. sound like a car engine that is firing too early 6. find fault with; express criticism of; point out real or perceived flaws. 
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(1) Don't knock that vase over.
(2) There was a treble knock at the door.
(3) I don't knock off until six.
(4) Knock on the door before you enter.
(5) Please knock on the door.
(6) They were interrupted by a knock at the door.
(7) Try not to knock that vase over.
(8) She hurried to answer the knock at the door.
(9) Can you knock this nail into the wood?
(10) When he heard the knock, he ceased writing.
(11) Just then there was a knock at the door.
(12) Did I hear a knock at the door?
(13) When her knock elicited no response , she opened the door and peeped in.
(14) Tell the servant to knock me up at five o'clock.
(15) I asked my father to knock me up at six o'clock.
(16) Life will knock us down, but we can choose whether or not to stand back up.
(17) It sounds as though there is a knock at the door.
(18) Knock before you enter.
(19) The builders can knock through to make one large room upstairs.
(20) If you knock the ball with your hand in football, you will suffer a penalty.
(21) Sometimes the world tries to knock it out of you, but I believe in music the way that some people believe in fairy tales.
(22) The racoons knock over the rubbish bins in search of food, and strew the contents all over the ground.
(23) The players have a couple of minutes to knock up before the match starts.
(24) Please have the civility to knock before you enter next time.
(25) His dad would beat/knock/kick the shit out of him if he disobeyed.
(26) You will never have a quiet world until you knock the patriotism out of the human race. Sentencedict.com
(27) If you don't tell me where you got that money, I'll knock the living daylights out of you!
(28) He diagnosed the trouble that caused the engine to knock.
(29) To get the plant out of the pot, turn it upside down and give it a gentle knock.
(30) It took a whole day of hard effort to knock down the wall.
More similar words: knock out, knock off, knock down, know, on occasion, sock, dock, know about, well known, well-known, shock, block, stock, hockey, rocket, cocked, acknowledge.