The traditional ontological division between the lexicon and grammar has often resulted in a reductionist view of the lexicon and lexical competence as composed of individual words in isolation. This narrow view of the lexicon has transcended disciplinary boundaries and is apparent in the focus on single words of widely used psycholinguistic measures of language (e.g. picture naming, verbal fluency, lexical decision) and cognitive ability alike (e.g. Stroop, recall in working memory span). This article argues that such an approach has imposed limitations on the questions that can be examined by researchers and on the generalizability of some results. Here I propose that, rather than assigning multiword units their own ‘niche’ in psycholinguistic studies, they should be viewed as part of the way core lexical competence is measured and conceptualized, both in monolingual and bilingual speakers. I also review promising advances in recent years brought about by a surge in the number of studies focused on multiword units and by new tasks of individual cognitive skill (e.g. multiword-based chunking ability). These hold the potential to allow for a cross-disciplinary shift in the examination of lexical competence as grounded in community-based norms and in line with current usage-based approaches.