#1 break down v. make ineffective; "Martin Luther King tried to break down racial discrimination". wn #2 break down v. make a mathematical, chemical, or grammatical analysis of; break down into components or essential features; "analyze a specimen"; "analyze a sentence"; "analyze a chemical compound". wn #3 break down v. lose control of one's emotions; "When she heard that she had not passed the exam, she lost it completely"; "When her baby died, she snapped". wn #4 break down v. stop operating or functioning; "The engine finally went"; "The car died on the road"; "The bus we travelled in broke down on the way to town"; "The coffee maker broke"; "The engine failed on the way to town"; "her eyesight went after the accident". wn #5 break down v. fall apart; "the building crumbled after the explosion"; "Negotiations broke down". wn