This chapter describes one entry point into conversations about language: the “citizen sociolinguistic arrest,” that is, the act of calling someone out for their use of language. An arresting citizen sociolinguist might be heard saying, “Don’t speak Spanish!” “Please call me Professor,” or simply, “Watch your language!” We can learn from citizen sociolinguistic arrests – not by immediately presuming ourselves guilty or innocent, but by allowing the moment to launch us on a pathway of inquiry. The chapter then models this inquiry approach – this doing of citizen sociolinguistics – by exploring the multiple contexts of meaning for the word citizen. The chapter takes readers through a citizen sociolinguist inquiry of the word citizen, exploring conversations about the word citizen, face-to-face, in the research literature, and on internet-circulated social-media, focusing on the kind of expertise that comes from conversations (and disagreements) about the word. This tour through the dramatic differences in how people talk about the word citizen illustrates an important interplay not only among assumptions underpinning different understandings of the word citizen, but also about the implied contexts that afford and perpetuate those assumptions. Each of these views of the word offers a slice of situated expertise.