for a fact

for a fact

Definitively; with certainty. I know for a fact that he cheats in cards! I saw the ace up his sleeve. My mom says she knows for a fact that I'm getting the internship at her company, but I won't believe it until the recruiter calls me.
See also: fact, for
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.
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