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noun sub·stance \ˈsəb-stən(t)s\

Simple Definition of substance

  • : a material of a particular kind

  • : a drug that is considered harmful and whose use is controlled by law or made illegal

  • : the quality of being meaningful, useful, or important

Source: Merriam-Webster's Learner's Dictionary

Full Definition of substance

  1. 1a :  essential nature :  essenceb :  a fundamental or characteristic part or qualityc Christian Science :  god 1b

  2. 2a :  ultimate reality that underlies all outward manifestations and changeb :  practical importance :  meaning, usefulness <the…bill—which will be without substance in the sense that it will authorize nothing more than a set of ideas — Richard Reeves>

  3. 3a :  physical material from which something is made or which has discrete existenceb :  matter of particular or definite chemical constitutionc :  something (as drugs or alcoholic beverages) deemed harmful and usually subject to legal restriction <possession of a controlled substance> <substance abuse>

  4. 4 :  material possessions :  property <a family of substance>


play \-ləs\ adjective

in substance

  1. :  in respect to essentials :  fundamentally

Examples of substance in a sentence

  1. The pancreas secretes a substance called insulin.

  2. The floor was covered with a white, powdery substance that turned out to be flour.

  3. heroin and other illegal substances

  4. He had a history of substance abuse.

  5. When has he ever said anything of substance?

  6. The results of the study give substance to their theory.

  7. the substance of my argument

Origin and Etymology of substance

Middle English, from Anglo-French, from Latin substantia, from substant-, substans, present participle of substare to stand under, from sub- + stare to stand — more at stand

First Known Use: 14th century

SUBSTANCE Defined for Kids


noun sub·stance \ˈsəb-stəns\

Definition of substance for Students

  1. 1 :  material of a certain kind <an oily substance>

  2. 2 :  the most basic or important part or quality <The books differ in both style and substance.>

  3. 3 :  material belongings :  wealth <a person of substance>

Medical Dictionary


noun sub·stance \ˈsəb-stən(t)s\

Medical Definition of substance

  1. 1:  physical material from which something is made or which has discrete existence <the substance of nerve tissue>

  2. 2:  matter of particular or definite chemical constitution

  3. 3:  something (as alcohol, methamphetamine, or marijuana) deemed harmful and usually subject to legal restriction <heroin is a controlled substance> <substance abuse>

Law Dictionary


noun sub·stance

Legal Definition of substance

  1. 1 :  substantive law <was a question of substance and not process> — compare procedure

  2. 2 :  something (as language) essential especially to establishing a valid right, claim, or charge <a title defective in form, not substance>

Seen and Heard

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to make consistent or congruous

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