he article discusses the processes of assimilation of plural noun forms borrowed from Latin and ending in -a in Swedish. An analysis based on the material from the Corpus of Swedish demonstrates that these processes have been caused by lexicalization and are accompanied by the appearance of variation in inflectional forms not only in the plural, but also in the singular. The borrowed Latin plural noun forms with collective meaning form two groups of lexemes in Swedish. One of them belongs to pluralia tantum: humaniora ‘the humanities’, personalia ‘biographical data’, antecedentia ‘antecedents’, spirituosa ‘spirits’, stimulantia ‘stimulants’, psykofarmaka ‘psychodrugs’. The latter two words show a tendency towards singularization and variation in gender attribution. In other lexemes the Latin plural forms have been reanalyzed and are interpreted as singular forms of common gender nouns with the stem in -a: kosmetika ‘cosmetics’, rekvisita ‘properties’, kontenta ‘gist’, prestanda ‘performance’, agenda ‘agenda’, petita ‘demand for funding’.
Nouns with the suffix -um belong to neuter gender and are inflected primarily according to the Swedish pattern: ett datum ‘date’, faktum ‘fact’, centrum ‘centre’, spektrum ‘spectrum’, kuriosum ‘curiosity’. The lexicalization of Latin plural noun forms can be observed when they refer to an indiscrete collective multitude and in most cases leads to singularization. Forms fakta, centra and spektra are used in the singular with markers of neuter gender; fakta can also be used with markers of common gender. The lexicalization of the Latin plural pattern with the marker -a in Swedish and its reanalysis as a singular form reveals a high degree of variation not only in noun inflection, but also in markers of coordination in adjectival parts of speech.