What is a deponent verb? Why do we have verbs which have only a Non Active morphology and never an Active one? Is it possible to these verbs as a coherent category, with a common feature? Is this common feature a syntactic one, a semantic one or a morphological one? I’m trying to propose a (partial) answer to these questions. To do that, I have analysed the most salient and representative Latin deponent verbs in the Latin texts of the first century BCE. The proposed analysis is a syntactic-semantic one. The issue of deponent verbs is inextricably bound to the Latin passive morphology (-r). I claim that -r is a Voice° deactivator, like German sich in anticausatives and middles and Italian si. This analysis is sustained by its distribution and syntactic-semantic features. A deactivated Voice° can convey an anticausative interpretation, a middle-passive or a reflexive (through Argument Identification). The only productive class of deponents in Latin is the denominal one and there is an obvious relationship between Voice° deactivation and deponents. In the derivation(s) of denominal deponents a deactivated Voice° is needed. Without it the Int Arg, merged with the verbalized noun (nP), could not gain the Ext Arg (initiator) semantics. The bridge between these two positions is built by Argument Identification, a semantic mechanism that relies on the presence of the deactivated Voice° and, consequently, on the -r morphology.