Substantius

Substantius is a historical term found in Latin literature used to describe things pertaining to substance or essence. The form derives from Latin substantia 'substance' with the adjectival suffix -ius, yielding roughly 'substantial' or 'pertaining to substance'. In philosophical and scholastic contexts, substantius is used to distinguish the essential or substantial aspect of a thing from its contingent or accidental properties. It may appear in discussions of what constitutes the being of a thing, where a distinction is drawn between substantive (substantive) qualities and incidental attributes.

In linguistic and grammatical contexts, substantius has occasionally been used in older texts to designate nouns or substantive elements of discourse, aligning with the sense of 'substantive' in English. In those sources, the term signals material that bears within a sentence as a subject or object, rather than modifiers or adjectives.

Today, substantius is largely obsolete outside of studies of Latin linguistic and philosophical terminology. It is encountered primarily in historical discussions of scholastic logic, metaphysics, and grammar, rather than as a current technical term.

See also: substantia, substantial, substantive, noun (grammar).