In this paper we develop an inferential account on the meaning and reference of theoretical concepts in physics, mainly based on the pragmatic notion of ‘inferential validity’. Firstly, we distinguish between empirical meaningfulness and theoretical significance as two different modes of meaning, wherein the former depends on consistently encoding experimental values, as proposed by Chang, and the latter on being semantically coherent with other concepts. Secondly, we argue that each of these contributions to the validity of inferences imports a causal (...) and representational mechanism of reference-fixing, respectively. Finally, we will rely on entropy concepts as our case study. (shrink)