Varronian etymology is largely in the tradition of Hellenistic etymology. Varro, however, intends to master the shortcomings of the speculative etymology of the Stoa. On the highest level of etymology (quartus gradus: LL V.8) he aims to clarify the etymological relation postulated between two words by construing a prehistoric form of the word to be explained. The diachronic phonological changes assumed by Varro are, on the whole, relatively little out of place. Their plausibility is due to the fact that Varro derives his sound changes from concrete linguistic data of Latin (i.e., older forms plus synchronic variants). Varro relies on empirical linguistic data within the framework of the reconstructive method, which he shares with his Greek contemporaries Philoxenos and Tryphon, whose phonological ‘pathology’ was, however, based on analogy and Greek dialectology. Varro’s modernity consists, above all, in the empirical character of his reconstructive method.