Through examination of one recently manufactured term for language learners (Long-term English Learners) and review of a century of "MLJ" articles, we examine varying "socioinstitutional" conceptualizations of second/foreign/heritage language learners as shaped by educational institutions and related stakeholders over time, given evolving understandings of the practice of language teaching that are directly related to theoretical, political, and institutional discourses. We focus very specifically on constructions of language learners that reflect different views and definitions of language learning, language acquisition/development, and ultimate attainment, examining the intersections of these definitions with formalized language instruction as a particularly significant force for learner categorizations. We argue that formalized language instruction both creates and requires categorizations/classifications of learners that are not neutral and that often have life-impacting consequences for individuals. These constructions of learners, moreover, are shaped by a number of interacting and intersecting mechanisms, including theoretical perspectives, educational policies, informing disciplines, instructional materials, pedagogical traditions, and testing and accountability requirements.