<p>A long-standing assumption in the language sciences is that the mental representation of language is based on constituents—that is, hierarchical structures rooted in grammar. We provide evidence from English for a more basic kind of linguistic representation involving smaller, linear chunks of structure akin to sequences of parts-of-speech elements—such as <span>verb preposition determiner</span> shared between the strings <i>added to a</i> and <i>defined by the</i>. Across four preregistered phrasal decision experiments (total <i>N</i> = 497), we show that it is possible to prime such linear structures, even in the absence of constituents. In two additional corpus analyses of eye-tracked reading (<i>N</i> = 68) and conversation (<i>N</i> = 358), we establish the external validity of the effect. These results provide evidence of multiword language structures that are not explainable in terms of constituents as traditionally construed. This poses a challenge for accounts of linguistic representation, including generative and constructionist approaches.</p>