- Exacting, unsparing - Harsh, severe - Rigidly severe - Severe or harsh - 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. - Severe; intense; inclement; as, a rigorous winter. - Violent.