Knock down

n.	1.	To strike down; to fell; to prostrate by a blow or by blows; as, to knock down an assailant.
	2.	To assign to a bidder at an auction, by a blow or knock of the auctioneer's hammer; to sell at an auction; as, the vase was knocked down at two thousand dollars.
	3.	To take apart; to dissassemble; as, to knock down a rifle for cleaning.
	4.	To reduce or discount the price of; as, the dresses were knocked down to twenty dollars.
	5.	To earn (an income).

Verb	1.	knock down - cause to come or go down; "The policeman downed the heavily armed suspect"; "The mugger knocked down the old lady after she refused to hand over her wallet" Synonyms: push down, pull down, cut down, down
	2.	knock down - knock down with force; "He decked his opponent" Synonyms: coldcock, floor, deck, dump

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