A constitution is an aggregate of fundamental principles or established precedents that constitute the legal basis of a polity, organisation or other type of entity and commonly determine how that entity is to be governed.
A system, often a written document, which establishes the rules and principles by which an organization, or political entity, is governed.
The formal or informal system of primary principles and laws that regulates a government or other institutions.
A law or system of laws which forms the foundation of a government, corporation or other organization's body of rules. A constitution is a particular form of organic law for a sovereign state.