Abstract
The article is concerned with the Latin s-stem deverbative neuters of the type genus, -eris, resp. decus, -oris. The first part of the article gives a summary of the present knowledge, both semantic and formal, of this Indo-European word-formative type.
The second part then analyses relevant Latin nouns, articulating the hypothesis that the nouns in -us, -eris, and -us, -oris are not originally the same formations, as has been presumed so far, but that they could be semantically (nomina rei actae/resultatives × outer subject affected by action) and formally (older proterodynamic × younger acrostatic nouns) distinguished.