To ascertain is to find out something for sure by checking, asking, or investigating. It means turning a guess into a fact.
From Anglo-French “acertener” meaning “to make certain,” from “a-” (to) and “certain.” It originally meant making something definite or settled.
Ascertain is the word for when curiosity puts on a lab coat. Instead of just wondering, you actually go and pin the truth down so it can’t wiggle away.
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