Plant-based products are increasing in popularity, as growing numbers of people choose plant-based lifestyles and eschew animal-based products. Strict laws govern the language that can be used to describe such products, however, both within the EU and in the UK. Against this backdrop, this paper employs mixed methods to provide analysis of the ways an-imal-based and plant-based ‘dairy’ products are packaged, marketed, retailed, and discussed in the UK. Using an approach rooted in Critical Discourse Analysis (CDA), it presents qualitative exploration of the means, both linguistic and multimodal, by which producers and retailers negotiate proscriptive legislation, as well as quantitative, corpus-based, analysis of lexis chosen to denote some plant-based products in internet discourse. Triangulating these methodological approaches, this study reveals an apparent disparity between vernacular UK usage in relation to plant-based dairy and how these products can be labelled in commercial contexts. Computer-assisted linguistic analysis provides quantitative means of analysing us-age, whilst qualitative techniques enable detailed consideration of different ways prescrip-tivism in this domain is interpreted and negotiated. This provides a holistic consideration of the impact legal prescription of certain linguistic variants has on commercial and individual usage, as well as demonstrating the value of critically-engaged approaches to prescriptivism.