- (a.) Manifesting, exercising or favoring rigor; allowing no abatement or mitigation; scrupulously accurate; exact; strict; severe; relentless; as, a rigorous officer of justice; a rigorous execution of law; a rigorous definition or demonstration.
- (a.) Severe; intense; inclement; as, a rigorous winter.
- (a.) Violent.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). Rigorous. Retrieved September 22, 2026, from http://smartdefine.org/rigorous/definitions/2056065 |
| Chicago | Webster's. 2011. "Rigorous" http://smartdefine.org/rigorous/definitions/2056065 (accessed September 22, 2026). |
| Harvard | Webster's 2011, Rigorous, Smart Define, viewed 22 September, 2026, <http://smartdefine.org/rigorous/definitions/2056065>. |
| MLA | Webster's. "Rigorous" 28 May 2011. Web. 22 September 2026. <http://smartdefine.org/rigorous/definitions/2056065> |