The paper focuses on the description of the approach, taken within the ESPRIT BRA project ACQUILEX, towards: i) acquisition of semantic information from several machine- readable dictionaries (in four languages), and ii) its representation in a common Lexical Knowledge Base. Knowledge extraction is guided by a) empirical observations and b) theoretical hypotheses. As for representation, we stress the convergence of a) and b) towards the possibility of organizing the information extracted from MRDs in the form of 'meaning types' or 'templates', where a common metalanguage is used to encode conceptual and relational information. Examples taken from two Italian monoUngual dictionaries and from LDOCE are given. Different uses of these templates (e.g. as guides in the semantic analysis of the definitions, as a structure for comparing, unifying, merging, integrating information coming from different sources and different languages, as a tool for correcting 'incohere...