1. Substantial; considerable. 2. Independent in existence or function; not subordinate. 3. Not imaginary; actual; real. 4. Of or relating to the essence or substance; essential: substantive information.5. Having a solid basis; firm. 6.Grammar Expressing or designating existence; for example, the verb to be.7.Grammar Designating a noun or noun equivalent.
NOUN:
Grammar A word or group of words functioning as a noun.
ETYMOLOGY:
Middle English substantif, self-sufficient, independent, from Old French, substantive, from Late Latin substantvus, from Latin substantia, substance. See substance.