This paper studies the semantics of multi-word expressions in early modern Scots legal discourse. The analyzed data was drawn from the Helsinki Corpus of Older Scots. The findings suggest that there is an unmistakably definable group of multi-word units in early modern legal texts, binomials (e.g., assent and consent), whose function and meaning are not derived from their individual constituents’ semantic relationships. The repetitive character exhibited by the constituents does not seem to be driven by precision of expression. Semantically unmotivated multi-word units are the most frequent ones in the corpus. Unlike suggested by previous discussions of legal vocabulary, semantic motivation is observed in a limited group of multi-word units.