break down

verb

1. make ineffective"Martin Luther King tried to break down racial discrimination"
2. make a mathematical, chemical, or grammatical analysis of; break down into components or essential features"analyze a specimen"
3. lose control of one's emotions"When she heard that she had not passed the exam, she lost it completely"
4. stop operating or functioning"The engine finally went"
5. fall apart"the building crumbled after the explosion"
6. cause to fall or collapse
7. separate (substances) into constituent elements or parts
8. collapse due to fatigue, an illness, or a sudden attack