Which term describes the established rules that govern the procedure of meetings within an assembly?

The term that describes the established rules governing the procedures of meetings within an assembly is "Rules of Order." These rules provide a systematic framework for conducting meetings in an orderly manner, ensuring that all members have the opportunity to participate effectively. Rules of Order cover various aspects of meeting procedures, including how motions are made, how discussions are managed, and the process for voting.

Bylaws typically are the governing documents that set forth the organization's framework and operational guidelines, while standing orders refer to specific rules that remain in effect until altered. A constitution outlines the fundamental principles or established precedents according to which a state or other organization is governed, but it does not specifically pertain to the procedural aspects of meetings like Rules of Order does. Therefore, "Rules of Order" is the correct answer as it directly addresses the procedures within an assembly during meetings.