- 1 [countable] an occasion when a vehicle or machine stops working a breakdown on the highway a breakdown recovery service
- 2[countable, uncountable] a failure of a relationship, discussion, or system the breakdown of a marriage marriage breakdown a breakdown in communications The breakdown of the negotiations was not unexpected. the breakdown of law and order
- 3[countable, usually singular] detailed information that you get by studying a set of figures First, let's look at a breakdown of the costs.
- 4[uncountable] (technology) the breaking of a substance into the parts of which it is made the breakdown of proteins in the digestive system
- 5[countable] = nervous breakdown She's still recovering from her breakdown.