The aim of this paper is to establish a semantic characterisation of vocatives, while leaving aside pragmatic and sociolinguistic considerations as far as possible. I will defend the `IPA-hypothesis' of the meaning of vocatives, that is, the hypothesis that vocatives have three basic functions: to identify the addressee(s), to predicate something on the addressee(s), and to activate the addressee(s). It will be argued that the traditional call vs. address dichotomy is insufficient.