Abstract I chart the philosophical development of neglected figure Margaret Macdonald and situate that development in the context of mid-century analytic philosophy more broadly. I examine Macdonald’s changing attitude towards verificationism, and show that these changing views led her, in 1950 and beyond, to a very thorough appreciation of language use as capable of being employed in the execution of distinctive kinds of performative act. I compare Macdonald’s views with the far better known work of J. L. Austin, and I emphasise the extent to which she has, despite her insightful contributions, been omitted from the history of philosophy.