Children's language development is a core task in Swedish preschool and central to how educators organize teaching and everyday activities. The curriculum's definition of language is described as extended, with language as both a prerequisite for learning and a learning effect, i.e. both internal processes and communication. This means that working methods and didactic strategies rely on many different epistemologies and thus different theoretical perspectives. Nevertheless, the research literature, as well as assessments of Swedish preschool services, show that educators' interpretation of the curriculum is primarily socioculturally oriented. This does not entirely converge with how language is conceptualized in the Swedish preschool curriculum. Against this background, the aim of this paper is to perform a theoretical and empirical investigation of the extended language concept in the curriculum with the intention to understand what the consequences of this extended meaning of language produce in terms of teaching and learning practices. I have traced various epistemologies in language didactic preschool research and related this tracing analysis to empirical examples from preschool practices. The results of my analysis show that the practices are predominantly interpersonally framed, which corresponds to the emphasis in research. In a further analysis, where empirical examples are read from other possible epistemologies, the practices can be perceived as being multi-epistemological in a fashion which corresponds to the curriculum's conceptualization of language. This is discussed as an opportunity for a didactic strengthening of presently neglected perspectives.