tr.v. as·cer·tained, as·cer·tain·ing, as·cer·tains
1. To discover with certainty, as through examination or experimentation. See Synonyms at discover.
2. Archaic To make certain, definite, and precise.
[Middle English acertainen, to inform, from Old French acertener, ascertain- : a-, to (from Latin ad-; see AD-) + certain, certain; see CERTAIN.]
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