Something substantial is large in size, number, or amount: If you want to say someone spent a lot of money without being too specific, you could say they spent a substantial amount of money.

The adjective substantial derives from the Latin substantia "substance," which means "stuff." A substantial meal is large enough to satisfy hunger. A substantial structure is strongly made or built. And a substantial man possesses wealth and property. Related to this last sense, "a man of substance" refers to a wealthy man with property.

Definitions of substantial
  1. adjective
    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”
    synonyms: material, real
    derived from or composed of matter
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    insubstantial, unreal, unsubstantial
    lacking material form or substance; unreal
    aerial, aeriform, aery, airy, ethereal
    characterized by lightness and insubstantiality; as impalpable or intangible as air
    shadowy, wraithlike
    lacking in substance
    consisting of or containing string or strings
    immaterial, nonmaterial
    not consisting of matter
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  2. adjective
    having a firm basis in reality and being therefore important, meaningful, or considerable
    substantial equivalents”
    synonyms: substantive
    basic and fundamental
  3. adjective
    of good quality and condition; solidly built
    “several substantial timber buildings”
    synonyms: solid, strong
    in good condition; free from defect or damage or decay
  4. adjective
    providing abundant nourishment
    “ate a substantial breakfast”
    synonyms: hearty, satisfying, solid, square
    conducive to or characteristic of physical or moral well-being
  5. adjective
    fairly large
    “won by a substantial margin”
    synonyms: significant
    large or relatively large in number or amount or extent or degree
Word Family

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