<p>This paper offers a new account of polysemy, which can explain the intuitions that utterances of copredicative sentences like ‘lunch was delicious, but went on forever’ involve polysemous terms, that they are true in some contexts, and that the truth of such utterances depends on the extensions of the component parts of the sentence. The goal of the paper is to show that we need not make a choice between truth-conditional semantics and acknowledging that copredicative sentences are genuinely polysemous. Rather, truth-conditional semantics is compatible with polysemy. As a preliminary, we shall discuss some of the current accounts of copredicative sentences in the literature, and argue that the existing attempts to make sense of polysemy in the framework of a truth-conditional semantics suffer from a number of drawbacks. Beginning in Sect. ‘A New Truth-Conditional Account of Polysemy’, we offer our own account. We show that our own account can account for a wider range of polysemous expressions than existing proposals.</p>