What is the term for when two or more parties join together to form a majority in a national legislature?

The term for when two or more parties join together to form a majority in a national legislature is a Coalition Government. This arrangement typically occurs in parliamentary systems where no single party holds a clear majority after an election. By forming a coalition, parties combine their seats to create a governing majority, which enables them to pass legislation and maintain stability within the government.

A coalition government often reflects a compromise between the participating parties, allowing for diverse representation and the incorporation of various viewpoints within the legislative process. This can lead to more inclusive governance, as coalitions are generally formed to represent a broader range of the electorate's interests compared to a single-party majority.

In contrast, dominance refers to a situation in which one party exerts a strong influence over the legislature, potentially limiting the role of minority parties. Majoritarianism emphasizes the principle that the majority's preferences should shape governance, but it does not inherently involve the collaboration of multiple parties. Unification generally refers to the merging of entities or organizations rather than the specific political collaboration necessary to form a majority in a legislature.