Language teaching and learning is commonly considered as a research discipline that resides within the field of 'applied linguistics', at least in the way the field is conceptualized by English-speaking academia. However, if we consider language teaching and learning as practice, this fit is not as neat as it at first might appear. Teaching, learning and using an additional language is complex and multifaceted; it involves languages, cultures, learning, communication, identities, etc., which in turn are situated academically within a host of disciplines. Research in language teaching and learning is therefore transdisciplinary in the sense that multiple disciplines can provide different lenses through which to understand the same phenomena and to build new understandings of the object of interest. Moreover, as a field in which languages and cultures are inherently brought into contact, language teaching and learning is also at an intersection between disciplines that are conceptualized and developed differently in different languages and academic traditions. For example, 'language teaching' as a disciplinary area does not map well onto its French translation equivalent 'didactique des langues'. These interactions across academic traditions therefore represent an often unacknowledged form of transdisciplinarity. This contribution will examine how language teaching and learning can be informed by a transdisciplinary perspective in both these senses. In particular, it will focus on the idea of language learning from an intercultural perspective to examine how multiple disciplines and different disciplinary traditions contribute to shaping understanding of the field; it will also consider some of the challenges of bringing multiple disciplines to bear on this understanding.