| rigidity(noun, strain, pressure, firmness, protection) |
| constraint(noun, force, compulsion, intimidation) |
| hardness(noun, firmness, protection, severity, security) |
| rigor(noun, firmness, severity, harshness, strictness) |
| firmness(noun, severity, tension, harshness, toughness) |
| inflexibility(noun, firmness, protection, severity, security) |
| rigorousness(noun, difficulty, firmness, rigidity, inflexibility) |
| rigour |
| toughness(noun, difficulty, firmness, protection, security) |
| formality(noun, drive, reserve, firmness, severity) |
| harshness(noun, firmness, severity, conformity, strictness) |
| severity(noun, firmness, harshness, conformity, strictness) |
| confinement(noun, force, compulsion, intimidation) |
| drive(noun, force, compulsion, intimidation) |
| inclemency(noun, severity, harshness, conformity, strictness) |
| inelasticity(noun, protection, security, rigidity, hardness) |
| restraint(noun, force, compulsion, coldness, intimidation) |
| solidity(noun, firmness, protection, security, stability) |
| tension(noun, firmness, rigidity, tightness, tautness) |
| austerity(noun, firmness, severity, harshness, conformity) |