noun
plural -downs
a failure of a machine to function :an occurrence in which a machine (such as a car) stops working [count]
[count] :the failure of a relationship or of an effort to discuss something
a failure that prevents a system from working properly [count]
[count] :a sudden failure of mental or physical health that makes someone unable to live normally
the process or result of showing the different parts of something in order to understand it more clearly [count]
[noncount] :the process or result of separating a substance into simpler parts