Definition of knock | Bee Dictionary of English

n the sound of knocking (as on a door or in an engine or bearing)
the knocking grew louder
n negative criticism
n a vigorous blow
the sudden knock floored him
n a bad experience
the school of hard knocks
n the act of hitting vigorously
v deliver a sharp blow or push :"He knocked the glass clear across the room"
v rap with the knuckles
knock on the door
v knock against with force or violence
v make light, repeated taps on a surface
v sound like a car engine that is firing too early
v find fault with; express criticism of; point out real or perceived flaws
Don't knock the food--it's free

One indulger in Bangkok's knockoff market is reformed after a visit to the Thai capital's Museum of Counterfeit Goods.
Knock, Knock No More .
Michelle and Barack Obama knocked knuckles as he took the stage to claim the Democratic presidential nomination, bringing new attention to the high-five's celebratory successor.

Knock on cold start a pain, but likely no big deal
I have a 2003 Pontiac Vibe, which is basically a Toyota Matrix, with 135,000 miles on it. This past winter on a cold start it would knock for a minute or three, depending on how cold. A friend who is a GM technician said that it is a cold piston slap, and it will last for a long time. Now, because I am aware of the sound, I can faintly hear it this summer. Could it be anything else?
June 16, 2013 - Boston Herald
Baseball: Gilbert, Knock roll through Nevada
GILBERT — Keeping opponents off the basepaths serves a dual purpose for Gilbert pitcher Jordan Knock. It all but thwarts potential runs and allows him to keep his momentum moving forward.
June 13, 2013 - The Ames Tribune
Knock Knock Prevails over Copyright and Trademark Infringers in the United States and Internationally
Knock Knock, a leader in creating interesting, well-designed gift and stationery products with a distinctive voice and look, is proud to announce recent settlements with several co
June 11, 2013 - Business Wire via Yahoo! Finance

Lance Armstrong in The Canadian Press
Our chances took a knock today,Armstrong said. "I'm not going home, we'll stay in the race and keep trying."
Rick Perry in MiamiHerald.com
It's a big storm,Texas Gov. Rick Perry said. "I cannot overemphasize the danger that is facing us. It's going to do some substantial damage. It's going to knock out power. It's going to cause massive flooding."
Donald Tusk in New York Times
Poland wants to be in alliances where assistance comes in the very first hours of - knock on wood - any possible conflict,Prime Minister Donald Tusk said.

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