In this article an attempt is made to show the dependence between the accepted convention of linguistic description and the conception of the meaning of proper nouns that results from this convention. The three views most widespread in onomastic literature are shown, which result from the concept of logico-philosophical, semantic, or psycholinguistic convention: (1) proper nouns are deprived of meaning, because as linguistic signs they do not imply any characteristics of the objects denoted; (2) in proper nouns there exists minimal categorical meaning indicating the onomastic category (e. g., rzeka (river), góra (mountain)); (3) proper nouns, due to their individual designation, have the richest meaning, for they indicate the most characteristics of the objects designated. The varied comprehension of the term 'meaning' in linguistics is indicated - from the strictly semantic to looser connotations and encyclopedic knowledge. In a final section the possibilities are shown for greater differentiation of onomastic methodologies that reflect to a higher degree the differentiation of units within the class of proper nouns.