Related Clues:
- Harshness of rules
- Highest scientific standards
- Mathematical precision
- Extreme precision
- The state of being harsh and severe
- Quality of a challenging class
- Intellectual ___ (careful reasoning that holds up to scrutiny)
- Exacting standard
- American exactitude shown in stiff feature
- Excessive strictness
- Austerity that's new in author's son
- Quality of good scientific research