[1] : The Collaborative International Dictionary of English v.0.48

substantial \substan"tial\, a. f. substantiel, l.
   substantialis.
   1. belonging to substance; actually existing; real; as,
      substantial life. --milton.
      1913 webster

            if this atheist would have his chance to be real and
            substantial agent, he is more stupid than the
            vulgar.                               --bentley.
      1913 webster

   2. not seeming or imaginary; not illusive; real; solid; true;
      veritable.
      1913 webster

            if happinessbe a substantial good.    --denham.
      1913 webster

            the substantial ornaments of virtue.  --l'estrange.
      1913 webster

   3. corporeal; material; firm. "most ponderous and substantial
      things." --shak.
      1913 webster

            the rainbow appears to be a large substantial
            arch.                                 --i. watts.
      1913 webster

   4. having good substance; strong; stout; solid; firm; as,
      substantial cloth; a substantial fence or wall.
      1913 webster

   5. possessed of goods or an estate; moderately wealthy;
      responsible; as, a substantial freeholder. "substantial
      yeomen and burghers." --sir w. scott.
      1913 webster

[2] : WordNet (r) 2.0

substantial
     adj 1: fairly large; "won by a substantial margin" syn: significant
     2: being the essence or essential element of a thing;
        "substantial equivalents"; "substantive information" syn:
         substantive, in essence
     3: 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 syn: real, material
        ant: insubstantial
     4: providing abundant nourishment; "a hearty meal"; "good solid
        food"; "ate a substantial breakfast" syn: hearty, satisfying,
         solid
     5: of good quality and condition; solidly built; "a solid
        foundation"; "several substantial timber buildings" syn:
        solid, strong
see also:
significant substantive in essence real material insubstantial 
hearty satisfying solid strong 

[3] : Moby Thesaurus II by Grady Ward, 1.0

307 moby thesaurus words for "substantial":
   ab ovo, able to pay, absolute, abundant, actual, adequate,
   affluent, allegorical, ample, appreciable, ascendant,
   associational, authentic, authoritarian, authoritative, authorized,
   autocratic, balanced, barely sufficient, basal, basic, big,
   big-league, big-name, big-time, bigwig, bigwigged, binding, bodily,
   bumper, calculable, charismatic, charming, close, close-knit,
   close-textured, close-woven, clothed with authority, cogent,
   comfortable, commanding, commensurate, compact, compacted,
   competent, compressed, concentrated, concrete, condensed,
   congested, connotational, connotative, consequential, considerable,
   consistent, consolidated, constituent, constitutive, controlling,
   cool, corporal, corporeal, corresponding, crammed, crammed full,
   crowded, de facto, decent, definable, denotational, denotative,
   dense, dependable, dominant, double-barreled, due,
   duly constituted, durable, earthly, earthshaking, easy, effective,
   effectual, efficacious, elemental, elementary, eminent, empowered,
   enchanting, enough, equal to, essential, estimable, ex officio,
   expressive, extended, extensional, factual, faithful, faithworthy,
   fast, fiducial, figurative, firm, firm as gibraltar, fit, fleshly,
   for real, full of meaning, full of point, full of substance,
   fundamental, generous, genuine, gluey, good, good enough, good for,
   goodly, governing, grand, great, gross, gut, hard, healthy, heavy,
   heavyweight, hegemonic, hegemonistic, high-powered, historical,
   honest-to-god, huge, hylic, impenetrable, imperative, impermeable,
   imperturbable, important, impressive, in equilibrium, indicative,
   influential, intelligible, intensional, interpretable, invincible,
   jam-packed, jammed, just, key, landed, large, large-scale, lawful,
   leading, legal, legitimate, logical, magnetic, major, man-sized,
   massive, material, materiate, meaning, meaningful, meaty,
   metaphorical, mighty, minimal, minimum, momentous, monocratic,
   name, nonporous, nonspiritual, numberless, numerous, objective,
   of the essence, official, original, packed, palpable, personable,
   persuasive, phenomenal, physical, pithy, plenty,
   plenty good enough, pointed, ponderable, positive, potent,
   powerful, predictable, preeminent, pregnant, prestigious, primal,
   primary, primitive, principal, profitable, prominent, propertied,
   proportionate, prosperous, puissant, radical, ranking, readable,
   real, referential, reliable, reputable, respectable, rich, ruling,
   satisfactory, secular, secure, self-consistent, self-important,
   senior, sensible, sententious, serious, serried, significant,
   significative, sizable, sizeable, snug, solid, solvent, somatic,
   sound, stable, staunch, steadfast, steady, stout, strong, sturdy,
   suasive, substantive, successful, sufficient, sufficient for,
   sufficing, suggestive, suitable, superior, supreme, sure, surefire,
   symbolic, tall, tangible, telling, temporal, thick, thick-growing,
   thickset, tidy, totalitarian, transferred, true, trustworthy,
   trusty, undeniable, underlying, unfailing, unflappable,
   unflinching, unindebted, unshakable, unspiritual, unwavering,
   up to, valid, vast, veritable, viscid, viscose, viscous, wealthy,
   weighty, well, well-balanced, well-built, well-established,
   well-fixed, well-founded, well-grounded, well-heeled, well-off,
   well-to-do, winning, without nerves, world-shaking, worldly,
   worthwhile

Substantial >> S Words
Substantial, definition of term: Substantial
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