1.To render (a person) certain; to cause to feel certain; to make confident; to assure; to apprise. (Obs.) "When the blessed Virgin was so ascertained." "Muncer assured them that the design was approved of by Heaven, and that the Almighty had in a dream ascertained him of its effects."
2.To make (a thing) certain to the mind; to free from obscurity, doubt, or change; to make sure of; to fix; to determine. (Archaic) "The divine law... ascertaineth the truth." "The very deferring (of his execution) shall increase and ascertain the condemnation." "The ministry, in order to ascertain a majority... persuaded the queen to create twelve new peers." "The mildness and precision of their laws ascertained the rule and measure of taxation."
3.To find out or learn for a certainty, by trial, examination, or experiment; to get to know; as, to ascertain the weight of a commodity, or the purity of a metal. "He was there only for the purpose of ascertaining whether a descent on England was practicable."
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