Simple Definition of substantiate

from our Learner's Dictionary

substantiate

verb

substantiates; substantiated; substantiating
formal : to prove the truth of (something)
He offered no evidence to substantiate [=support] his claim.

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“Substantiate.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/substantiate. Accessed 20 Jun. 2026.

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