substantiate
v.to prove that something is true or real by providing facts or evidence. You use this when you want to show that a claim has a solid reason behind it.
v.to provide evidence or proof to support a claim, theory, or fact. Transitive — requires a direct object representing the claim or evidence.
“The scientist needs to substantiate his theory with new data.”
“The lawyer asked for documents to substantiate the claim that the company had broken the contract.”
“While the initial report suggested a significant drop in sales, the final audit failed to substantiate these figures, revealing that the decline was actually a minor seasonal fluctuation.”
“Anti-greenwashing rules generally ask whether claims are clear, accurate and substantiated.”
“If a claim is substantiated, the plagiarist is seen as sloppy or lazy at best, and fundamentally dishonest at worst.”
From Medieval Latin substantiatus (“given substance”), from the verb substantiare, first used 1657.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.