Antonyms - just like synonyms and homonyms - may affect each other's meanings, even though opposition does not have as important a role in meaning specification as synonymy or homonymy does. In forming pairs of opposites, both concrete and abstract ones, an important role is played by derivational suffixes of opposite functions. Denominal privative adjectives in -tlAn denoting 'lacking something' tend to contrast semantically with adjectives carrying the suffix -(V)s meaning 'being supplied with something' and/or with constructions suffixed by -(j)U, closely related to the former. Available definitions of the uses of -(V)s and -(j)U suggest that the privative forms should only contrast semantically with derivatives involving -(V)s, in view of the fact that it is only a 'part-whole' relationship that makes it possible to detach the 'part' from the 'whole'. Indeed, a prerequisite of the use of a privative suffix is that the 'part' should be an alienable part or property of the possessive argument bearing the subject role. The aim of this paper is a presentation and semantic analysis of pairs of antonyms, as well as their classification into categories based on the various notions of opposites (exclusive opposition, converseness, difference in degree) in semiotics. The author gives a detailed account of pairs of words in -tlAn vs. -(V)s derived from the same stem and hence antonymous in terms of the original semantics of their suffixes, noting that such derivatives in some cases have deviated from their original meanings (e.g., csinos 'pretty' - csintalan 'naughty', kedves 'kind' - kedvetlen 'dispirited', szemes 'cute' - szemtelen 'impertinent'), and she devotes special attention to privative doublets (emerging due to semantic fission) and their opposites (e.g., alomtalan 'dreamless' / almatlan 'sleepless' - almos 'sleepy', gondtalan 'carefree' / gondatlan 'careless' - gondos 'careful').