significant, substantial -- (fairly large; "won by a substantial margin")
substantial, substantive -- (having a firm basis in reality and being therefore important, meaningful, or considerable; "substantial equivalents")
substantial, real, material -- (having substance or capable of being treated as fact; not imaginary; "the substantial world"; "a mere dream, neither substantial nor practical"; "most ponderous and substantial things"- Shakespeare)
hearty, satisfying, solid, square, substantial -- (providing abundant nourishment; "a hearty meal"; "good solid food"; "ate a substantial breakfast"; "four square meals a day")
solid, strong, substantial -- (of good quality and condition; solidly built; "a solid foundation"; "several substantial timber buildings")
(Sound)
