| gumption |
| guttiness(noun, resolve, determination, firmness, persistence) |
| hardness(noun, support, control, strength, balance) |
| heroism |
| immobility(noun, support, control, strength, balance) |
| immovability(noun, support, control, strength, spirit) |
| independence(noun, drive, energy, resolve, determination) |
| indomitableness |
| inflexibleness |
| intent(noun, spirit, determination, resolution, firmness) |
| intention(noun, spirit, determination, resolution, firmness) |
| intestinal fortitude(noun, expression, resolve, determination, firmness) |
| intransigence(noun, resolve, determination, firmness, persistence) |
| iron will(noun, expression, idiom, resolve, determination) |
| manhood(noun, maturity) |
| manliness |
| maturity(noun, support, control, strength, balance) |
| obstinance(noun, resolve, determination, resolution, firmness) |
| patience(noun, strength, determination, courage, firmness) |
| pith(noun, strength, determination, courage, firmness) |