Definition of: knock

(nok) v.t.
1. To give a heavy blow to; hit.
2. To strike (one thing) against another; bring into collision.
3. To drive or impel by striking: to knock a ball over a fence.
4. To make or cause by striking: to knock a hole in a wall.
5. U.S. Slang To find fault with; carp at.
—v.i.
6. To strike a blow or blows, as with the fist or a club.
7. To come into collision; bump.
8. To make a pounding or clanking noise, as an engine.
9. U.S. Slang To find fault; carp.
—to knock about (or around)
1. To strike repeatedly; hit from side to side.
2. To wander from place to place.
3. To treat neglectfully; abuse.
—to knock down
1. To take apart for convenience in shipping or storing.
2. In auctions, to sell to the highest bidder.
3. U.S. Slang To embezzle a part of money passing through one's hands,
—to knock off
1. To leave off; stop, as work, talking, etc.
2. To deduct.
3. To do or make quickly or easily.
4. U.S. Slang To kill; also, to overwhelm or defeat.
—to knock out
1. In boxing, to defeat (an opponent) by striking him to the ground for a count of ten.
2. To render unconscious or exhausted.
—to knock out of the box In baseball, to hit the pitches of (an opposing pitcher) so often as to cause his removal from the game.
—to knock together To build or make roughly or hurriedly.
—to knock up
1. Brit. To rouse, as by knocking on the door.
2. Brit. Colloq. To tire out; exhaust.
3. U.S. Slang To make pregnant.
—noun
1. A sharp blow; a rap; also, a knocking.
2. Mech. a The noise produced in machinery or in engines when the operating parts are defective, badly worn, or poorly adjusted. b In an internal–combustion engine, the metallic explosive sounds due to uneven or improperly timed combustion.
3. U.S. Colloq. Hostile criticism; an adverse comment. [OE cnocian]