Interactional expertise is said to be a form of knowledge achieved in a linguistic community and, therefore, obtained entirely outside practice. Supposedly, it is not or only minimally sustained by the so-called embodied knowledge. Here, drawing upon studies in contemporary neuroscience and cognitive psychology, I propose that ‘derived’ embodiment is deeply involved in competent language use and, therefore, also in interactional expertise. My argument consists of two parts. First, I argue for a strong relationship among language acquisition, language use and (...) the real world (i.e. the world accessible to the senses). Biological constraints in very early childhood anchor language to the body. These constraints are by-products of our evolutionary peculiarity that we gain because of our physical and psychological immaturity at birth. Thus, infancy is predominantly concerned with the bodily needs and experiences of the concrete while language acquisition takes place. Particular interest in the concrete furnishes our linguistic world and installs ‘concrete’ language as the principal constituent of competent language use. Second, I argue that well-established concrete language implicitly and explicitly elicits mental representations, namely partial reactivations of sensorimotor states that occur during experience. These are stepping stones by which we subsequently make sense of expressions in new linguistic areas. Like any competent language user, the interactional expert, therefore, prompts multimodal imagination and re-enacts concrete experiences when acquiring linguistic knowledge pertaining to a specialist field. Finally, I outline the characteristics of those imaginative powers to identify mechanisms that improve interactional expertise and discuss the obvious relation between interactional expertise and ordinary knowledge acquisition after the concrete language stage. (shrink)