This paper reports on the main phases of a research which aims at enhancing a maritime terminological database by means of a set of terms belonging to meteorology. The structure of the terminological database, according to EuroWordNet/ItalWordNet model is described; the criteria used to build corpora of specialized texts are explained as well as the use of the corpora as source for term selection and extraction. The contribution of the semantic databases is taken into account: on the one hand, the most recent version of the Princeton WordNet has been exploited as reference for comparing and evaluating synsets; on the other hand, the Italian WordNet has been employed as source for exporting synsets to be coded in the terminological resource. The set of semantic relations useful to codify new terms belonging to the discipline of meteorology is examined, revising the semantic relations provided by the IWN model, introducing new relations which are more suitably tailored to specific requirements either scientific or pragmatic. The need for a particular relation is highlighted to represent the mental association which is made when a term intuitively recalls another term, but they are neither synonyms nor connected by means of a hyperonymy/hyponymy relation.