1.To strike with something hard or heavy; to move by striking; to drive (a thing) against something; as, to knock a ball with a bat; to knock the head against a post; to knock a lamp off the table. "When heroes knock their knotty heads together."
2.To strike for admittance; to rap upon, as a door. "Master, knock the door hard."
3.To impress strongly or forcibly; to astonish; to move to admiration or applause. (Slang, Eng.)
4.To criticise; to find fault with; to disparage. "Don't knock it if you haven't tried it."
To knock in the head, or To knock on the head, to stun or kill by a blow upon the head; hence, to put am end to; to defeat, as a scheme or project; to frustrate; to quash. (Colloq.) To knock off. (a)To force off by a blow or by beating.
(b)To assign to a bidder at an auction, by a blow on the counter.
(c)To leave off (work, etc.). (Colloq.) To knock out, to force out by a blow or by blows; as, to knock out the brains.
To knock up. (a)To arouse by knocking.
(b)To beat or tire out; to fatigue till unable to do more; as, the men were entirely knocked up. (Colloq.) "The day being exceedingly hot, the want of food had knocked up my followers."
(c)(Bookbinding) To make even at the edges, or to shape into book form, as printed sheets.
(d)To make pregnant. Often used in passive, "she got knocked up". (vulgar)
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