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Literature on the role of “chance” in evolutionary theory exhibits a dizzying array of claims – from “randomness” in genetic drift and mutation to “propensities” in fitness and “contingency” in macroevolution. I argue that much of this diversity is due to the persistent conflation of several senses of “chance,” and a corresponding failure to determine which sense is at issue in any particular biological instance. I offer an attempt to clarify and separate five of these senses: (i) the statistical or non-statistical character of a theory, (ii) the probabilistic or non-probabilistic character of a causal process, (iii) the determinism or indeterminism of underlying physics, (iv) the contingency or necessity of a historical process, and (v) the predictability or unpredictability of a particular system. I then conclude with an initial effort at showing how careful maintenance of these distinctions can enhance our understanding of the role of chance in evolution, by applying them to a few current debates in the philosophy of biology.