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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(211) If you carry on working like this, you'll knock yourself out.
(212) I was interrupted by a knock on the door and lost my train of thought.
(213) They were all laughing when there came a knock at the door.
(214) I can knock off a poem in half an hour.
(215) Leave the boy with me—I'll soon knock him into shape!
(216) Her confidence took a hard knock when her application was rejected.
(217) If you haven't made an appointment, take pot luck and knock on the door.
(218) I don't like the children playing in this room, for fear they knock the furniture around.
(219) He got a knock on the head when he fell.
(220) Jim will knock your block off if he catches you riding his bike.
(221) I was so involved in my book I didn't hear you knock.
(222) You'd better knock up for a while before starting the game.
(223) Knock the "t" off the "can't.". Samuel Johnson 
(224) Most of the people I knock about with are in the union.
(225) Perseverance is a great element of success. If you only knock long enough and loud enough at the gate,[sentencedict .com] you are sure to wake up somebody. Henry Wadsworth Longfellow
(226) No man ever got very high by pulling other people down. The intelligent merchant does not knock his competitors. The sensible worker does not work those who who work with him. Don't knock your friends. Don't knock your enemies. Don't knock yourself. Alfred Tennyson
(227) But there are plenty of things that threaten anew to knock Clinton off his presidential perch.
(228) Let's knock off now.
(229) Expecting the visitor to knock to gain admittance, the signalman walked towards the door to see what the visitor wanted.
(230) You'll never have a quiet world till you knock the patriotism out of the human race. George Bernard Shaw
(231) All over Ireland, posters advertise pilgrim coach tours to Knock, a town famous for apparitions of the Virgin Mary.
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.