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Synonyms

substantiate

American  
[suhb-stan-shee-eyt] / səbˈstæn ʃiˌeɪt /

verb (used with object)

  • substantiates,
    present (3rd person singular)
  • substantiated,
    past participle,  past
  • substantiating
    present participle
  1. to establish by proof or competent evidence.

    to substantiate a charge.

    Synonyms:
    validate, verify, confirm, prove
  2. to give substantial existence to.

    to substantiate an idea through action.

  3. to affirm as having substance; give body to; strengthen.

    to substantiate a friendship.


substantiate British  
/ səbˈstænʃɪˌeɪt /

verb

  1. to establish as valid or genuine

  2. to give form or real existence to

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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Etymology

Origin of substantiate

First recorded in 1650–60; from New Latin substantiātus (past participle of substantiāre ), equivalent to Latin substanti(a) substance + -ātus -ate 1

Explanation

To substantiate is to give support to a claim. We’d really like to believe in the Tooth Fairy; however, more evidence is needed to substantiate her existence (besides that quarter in your pocket). Substantiate is related to the word substantial, which means "solid." So, to substantiate a claim is to make it solid or believable. If the evidence given in support of an argument is weak and unconvincing, that evidence can be described as insubstantial. Of course, in special cases like the Tooth Fairy, having substantial evidence doesn’t seem to matter; fans just keep on believing.

Keep Reading on Vocabulary.com

Vocabulary lists containing substantiate

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Lillian Carranza said she understood why Flores “might feel compelled to gather evidence to substantiate serious allegations,” given how the department has handled past whistleblower cases.

From Los Angeles Times Aug. 7, 2026

Exhaustive reviews of the published science on raw milk have broadly been unable to substantiate claims of its benefits, and most experts agree that it is neither healthy nor safe to consume.

From Salon Jun. 22, 2026

Investigators ultimately said there was insufficient evidence to substantiate the allegations.

From BBC Jun. 9, 2026

Through these chart reviews, the DOJ alleges, Aetna identified opportunities for additional payments from the Medicare agency, yet ignored the results when the chart reviews didn’t substantiate codes Aetna had already submitted to the agency.

From Barron's Mar. 11, 2026

White hadn’t been able to substantiate Kenny’s allegations, but he wasn’t sure what to make of Comstock, either.

From "Killers of the Flower Moon" by David Grann

But recent data substantiates that the vaccine is highly effective and safe.

From Salon Feb. 22, 2026

And it substantiates the argument Sir Keir himself made in the House of Commons.

From BBC Feb. 11, 2026

“Not every criminal investigation substantiates evidence of a criminal violation of federal law,” she said.

From Seattle Times May 16, 2023

“We have put forward compelling and unrebutted factual evidence that substantiates his status,” attorney David Rivkin said.

From Washington Times Dec. 23, 2022

Your sister substantiates this failing for as her letter progresses her judgment gives way to temper—her thoughts are good, lucid the products of intelligence, but it is not now an unbiased, impersonal intelligence.

From "In Cold Blood" by Truman Capote

"No court, no agency has ever substantiated any allegation of abuse against me," Miller said in a video posted Sunday, insisting he would remain in the race and win.

From Barron's Aug. 3, 2026

The carmaker expects stronger revenue growth in the Middle East/Africa and Europe than consensus, with the outlook for Europe in particular needing to be substantiated, Jefferies says.

From The Wall Street Journal May 22, 2026

The anticipated decrease in heart disease was not substantiated, and, more alarmingly, they cited “excess harm.”

From MarketWatch May 12, 2026

The ASA does not comment on specific cases, but is taking steps against the advertisers flagged by the BBC which made claims that were "unlikely" to be substantiated.

From BBC May 7, 2026

Evidence Against Her or Suspicious Circumstances: Story of man in her compartment is substantiated by the evidence of Hardman and that of the woman Schmidt.

From "Murder on the Orient Express" by Agatha Christie

This watershed boxed set features cutting-edge remasters of the singer’s 1920s recordings, substantiating her centrality in blues and beyond.

From The Wall Street Journal Jul. 20, 2026

Ohio leaders including Republican Gov. Mike DeWine said they received no credible reports substantiating the rumors.

From Los Angeles Times Oct. 31, 2024

The New York Times has reviewed documentation substantiating her account.

From New York Times Mar. 16, 2024

The group put a lot of effort into substantiating RoboChem's results.

From Science Daily Jan. 25, 2024

After a lapse of several days I received from him a letter substantiating in detail all that was mentioned in the newspaper clipping quoted above.

From Tyranny of God by Joseph Lewis

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