- (v.t.) To render (a person) certain; to cause to feel certain; to make confident; to assure; to apprise.
- (v.t.) To make (a thing) certain to the mind; to free from obscurity, doubt or change; to make sure of; to fix; to determine.
- (v.t.) 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.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). ascertain. Retrieved September 21, 2026, from http://smartdefine.org/ascertain/definitions/1976193 |
| Chicago | Webster's. 2011. "ascertain" http://smartdefine.org/ascertain/definitions/1976193 (accessed September 21, 2026). |
| Harvard | Webster's 2011, ascertain, Smart Define, viewed 21 September, 2026, <http://smartdefine.org/ascertain/definitions/1976193>. |
| MLA | Webster's. "ascertain" 27 May 2011. Web. 21 September 2026. <http://smartdefine.org/ascertain/definitions/1976193> |