toughness

n. difficulty; intensity

In materials science and metallurgy, toughness is the resistance to fracture of a material when stressed. It is defined as the amount of energy that a material can absorb before rupturing, and can be found by taking the area (i.e., by taking the integral) underneath the stress-strain curve. The ability to with stand sudden loading. Toughness is measured in units of joules per cubic meter (J/m³) in the SI system and pound-force per square inch (sometimes expressed as in-lbf/in³) in US customary units.
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Noun
1. enduring strength and energy
(synonym) stamina, staying power
(hypernym) endurance
(hyponym) legs
2. the property of being big and strong
(synonym) huskiness, ruggedness
(hypernym) strength
3. the elasticity and hardness of a metal object; its ability to absorb considerable energy before cracking
(synonym) temper
(hypernym) elasticity, snap
4. impressive difficulty
(synonym) formidability
(hypernym) difficulty, difficultness

(n.)
The quality or state of being tough.
  

Synonyms and related words:
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, induration, 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