1. : the precedence or priority under the rules or practice of a deliberative or legislative body in which different proceedings, reports, motions, and general business will be considered or will take place
2. : a program or sequence of different matters or classes of business arranged in the order in which they are to be taken up by an assembly
3. : a matter or problem calling for attention or solution : task
the problem of congestion is the first order of business with the commission — S.H.Hofstadter