‘Biodiversity’ is widely recognized as an extremely ambiguous concept in conservation science and ecology. It is defined in a number of different and incompatible ways in the scientific literature, and is also “exported” beyond the scientific community, where it may take on a host of other meanings for governments, policy-makers, non-governmental organizations, and the general public at large. One might respond to this ambiguity by either pushing for its clarification, and by extension the adoption of a single, univocal biodiversity concept, (...) or by rejecting the term entirely, replacing it with a relevant, more precise concept in each context. In this paper, I argue for a third approach. Drawing on literature describing change in large organizations, I explore ways in which ambiguity might be seen as productive – as a manner, at the very least, in which we can enable action by a mixed coalition of actors with different and, at times, contradictory interests and value commitments. I explore how this literature – in particular, a taxonomy of rhetorical uses of ambiguous concepts – could enable us to put the ambiguity of biodiversity to work for us, offering us a way to intervene in conflicts about the concept by helping to develop both clearer descriptive analyses and normative “rules for engagement” in debates surrounding biodiversity. (shrink)