| forcefulness(noun, drive, power, strength, energy) |
| foundation(noun, law, substance, informal, basic) |
| fundamental(noun, part, informal, condition, essence) |
| gore |
| guttiness(noun, resolve, determination, firmness, persistence) |
| heart of hearts(noun, expression, idiom, emotion, mood) |
| heart of oak(expression, idiom, courage) |
| heroism(noun, spirit, dash, determination, courage) |
| hotness(sharpness, bitterness, spiciness) |
| impertinence(noun, spirit, face, rudeness, assurance) |
| impressiveness(noun, drive, power, strength, energy) |
| incisiveness(burn, edge) |
| indefatigability(noun, strength, energy, determination, resolution) |
| ingredients(inside, filling, innards) |
| inside(noun, pack, content, center, middle) |
| insolence(noun, order, disregard, strength, spirit) |
| intestine |
| intrepidness(noun, spirit, dash, courage, heart) |
| inwards |
| kick(noun, excitement, interest, hint, suggestion) |