1
                           general:: 
                            Phrase(s): knock someone or something down 
to thrust someone or something to the ground by hitting.  •  The force of the blast knocked us down.  •  It knocked down everyone in the room., Phrase(s): knock something down
1. Sl. to drink a portion of liquor.  •  Here, knock this down and let’s go.  •  He knocked down a bottle of beer and called for another. 2. Sl. to earn a certain amount of money.  •  I’m lucky to knock down twenty thousand.  •  She must knock down about twenty thou a year.
                        
                        
 
                        
                            McGrawhill's American Idioms And Phrasal Verbs
                        
                        
                    
                    
                        2
                           general:: 
                            1. Take apart for storage or shipping, as in We need to knock down this chest to ship it safely overseas. [Mid-1900s] 2. Declare sold at an auction, as by striking a blow with a gavel. For example, That was the last bid, and the first edition was knocked down for only three hundred. [Mid-1700s] 3. Reduce the price of, as in They knocked it down by another hundred dollars, or An overabundant harvest will knock down corn prices. [Colloquial; mid-1800]. 4. Earn as wages, as in She knocks down a hundred grand a year. [Slang; 1920s] 5. Steal, embezzle, as in He was caught knocking down the box-office receipts. This usage may be obsolescent. [Slang; mid-1800s]  Also see  KNOCK OVER, def. 2.
                        
                        
 
                        
                            American Heritage Idioms