of ample or considerable amount, quantity, size, etc.

a substantial sum of money.

of a corporeal or material nature; tangible; real.

of solid character or quality; firm, stout, or strong

a substantial physique.

basic or essential; fundamental

two stories in substantial agreement.

wealthy or influential

one of the substantial men of the town.

of real worth, value, or effect

substantial reasons.

pertaining to the substance, matter, or material of a thing.

of or pertaining to the essence of a thing; essential, material, or important.

being a substance; having independent existence.

Philosophy . pertaining to or of the nature of substance rather than an accident or attribute.

something substantial.