By extending the notion of metroethnicity, this paper proposes the notion of metrolingualism, creative linguistic practices across borders of culture, history and politics. Metrolingualism gives us a way to move beyond current terms such as "multilingualism" and "multiculturalism". It is a product of modern and often urban interaction, describing the ways in which people of different and mixed backgrounds use, play with and negotiate identities through language. The focus is not so much on language systems as on languages as emergent from contexts of interaction. Looking at data from workplaces where metrolingual language use is common, we show how the use of both fixed and fluid linguistic and cultural identities is part of the process of language use. The notion of metrolingualism gives us ways of moving beyond common frameworks of language, providing insights into contemporary, urban language practices, and accommodating both fixity and fluidity in its approach to language use. (Contains 3 notes.)