Every theory should begin with a definition of its basic concept. In versology this is clearly a verse. However, this technical term has not had the best fortune in Slovene literary theory. In Slovene literary and linguistic lexicons a verse is ususally defined as a line, an not as a particular kind of artistic discourse, different from prose. The paper does not attempt to tackle the realm of content, Its goal is not to define a border between poetry and prose, but rather between verse and prose; and this border, if it exists, is certanly somewhere on the formal level.