American Dictionary of the English Language

SUB'STANTIVE, adjective Betokening existence; as the substantive verb.

1. Solid; depending on itself. [Not in use.]

SUB'STANTIVE, noun In grammar, a noun or name; the part of speech which expresses something that exists, either material or immaterial. Thus man, horse, city, goodness, excellence, are substantives. [Better called name, Latin nomen, or even noun, a corruption of nomen.]