Definition of break down phrasal verb from the Oxford Advanced Learner's Dictionary

Language BankillustrateReferring to a chart, graph or table This bar chart illustrates how many journeys people made on public transport over a three-month period. This table compares bus, train, and taxi use between April and June. The results are shown in the chart below. In this pie chart, the survey results are broken down by age. This pie chart breaks down the survey results by age. As can be seen from these results, younger people use buses more than older people. According to these figures, bus travel accounts for 60% of public transport use. From the data in the above graph, it is apparent that buses are the most widely used form of public transport.Phrasal Verbs
  1. 1  (of a machine or vehicle) to stop working because of a fault The telephone system has broken down. We (= the car) broke down on the freeway. related noun breakdown See related entries: Motoring problems and accidents, How machines work
  2. 2  to fail Negotiations between the two sides have broken down. related noun breakdown
  3. 3to become very bad Her health broke down under the pressure of work. see also nervous breakdown
  4. 4  to lose control of your feelings and start crying He broke down and wept when he heard the news.
  5. 5to divide into parts to be analysed Expenditure on the project breaks down as follows: wages $10m, plant $4m, raw materials $5m. related noun breakdown
  1. 1  to make something fall down, open, etc. by hitting it hard Firefighters had to break the door down to reach the people trapped inside.
  2. 2to destroy something or make it disappear, especially a particular feeling or attitude that somebody has to break down resistance/opposition to break down somebody’s reserve/shyness Attempts must be made to break down the barriers of fear and hostility which divide the two communities.
  3. 3to divide something into parts in order to analyse it or make it easier to do Break your expenditure down into bills, food and other. Each lesson is broken down into several units. related noun breakdown
  4. 4to make a substance separate into parts or change into a different form in a chemical process Sugar and starch are broken down in the stomach.
  5. related noun breakdown
See the Oxford Advanced American Dictionary entry: break down