Chapter 3 explores the interpretive stasis of definition, where there is a question concerning the intended or appropriate scope of the basic sense of a term in a text. The chapter shows how rhetors, by persuasively articulating a definition and resorting to various lines of argument, can shift the meaning of passages and reframe controversies hinging on a text’s interpretation by adjusting the scope of a single term. But only linchpin terms (similar to Burke’s and Weaver’s ultimate terms) have this governing quality. The chapter’s central example consists of oral arguments from the 2010 Supreme Court case McDonald v. City of Chicago that ultimately determined US citizens have a fundamental right to bear arms. The case partly rested on whether the Fourteenth Amendment’s phrase privileges or immunities, generally protected from state infringement, includes this right within its scope. The centrality of definitional disputes to legal interpretation is also considered.