toughness, spartanism, abstruseness, adamantness, adhesiveness, arduousness, astringency, austerity, authoritarianism, backbone, body, bothersomeness, bottom, bullheadedness, burdensomeness, callosity, callousness, chutzpah, clabbering, clamminess , clotting, coagulation, cohesiveness, colloidality, complexity, complication, concreteness, consistency, courage, curdling, decisiveness, demandingness, density, difficultness, difficulty, discipline, doughiness, dourness, durability, durity, endurance, energy, exactingness, firmness, flintiness, force, fortitude, gameness, gelatinity, gelatinousness, gluelikeness, gluiness, glutinosity, glutinousness, grimness, grit, gumlikeness, gumminess, guts, gutsiness, guttiness, hairiness, hard-bittenness, hard-nosedness, hardiness, hardness, hardness of heart, harshness, heart, heart of oak, heartiness, heaviness, immovability, immutability, impenetrability, implacability, impliability, incrassation, inelasticity, inexorability, inflexibility, inspissation, intestinal fortitude, intransigeance, intransigence, intransigency, intransigentism, intricacy, irreconcilability, jellification, jellylikeness, laboriousness, lentor, lustihood, lustiness, mass, materiality, meticulousness, mettle, mettlesomeness , might, mightiness, moxie, mucilaginousness, nerve, obduracy, obstinacy, onerousness, oppressiveness, palpability, pastiness, persistence, persistency, pith, pluck, pluckiness, ponderability, potency, power, powerfulness, regimentation, relentlessness, resistance, restiveness, retention, rigid discipline, rigidity, rigor, rigorism, rigorousness, robustness, ropiness, ruggedness, severity, slabbiness, sliminess, snugness, solidity, soundness, spirit, spissitude, spunk, spunkiness, stability, stalwartness, stamina, staying power, steadiness, steeliness, sternness, stick-to-itiveness, stickiness, sticking power, stiff temper, stiffness, stodginess, stoniness, stout heart, stoutness, strength, strength of will, strenuousness, strictness, stringency, stringiness, stubbornness, sturdiness, substance, substantiality, substantialness, syrupiness, tackiness, tangibility, tenaciousness, tenacity, thickening, thickness, tightness, toilsomeness, treacliness, troublesomeness, true grit, unalterability, unbendingness, unchangeability, uncompromisingness, ungivingness, unrelentingness, unyieldingness, vigor, vigorousness, viscidity, viscosity, viscousness, vitality