guts(n = noun.attribute) backbone, grit, gumption, moxie, sand - fortitude and determination; "he didn't have the guts to try it"
is a kind of fortitude
Derived form adjective gutsy1
N courage, bravery, valor, resoluteness, boldness, spirit, daring, gallantry, intrepidity, contempt of danger, defiance of danger, derring-do, audacity, rashness, dash, defiance, confidence, self-reliance, manliness, manhood, nerve, pluck, mettle, game, heart, heart of grace, spunk, guts, face, virtue, hardihood, fortitude, intestinal fortitude, firmness, heart of oak, bottom, backbone, spine, resolution, bulldog courage, prowess, heroism, chivalry, exploit, feat, achievement, heroic deed, heroic act, bold stroke, man, man of mettle, hero, demigod, Amazon, Hector, lion, tiger, panther, bulldog, gamecock, fighting-cock, bully, fire eater, courageous, brave, valiant, valorous, gallant, intrepid, spirited, spiritful, high-spirited, high-mettled, mettlesome, plucky, manly, manful, resolute, stout, stout-hearted, iron-hearted, lion-hearted, heart of oak, Penthesilean, bold, bold-spirited, daring, audacious, fearless, dauntless, dreadless, aweless, undaunted, unappalled, undismayed, unawed, unblanched, unabashed, unalarmed, unflinching, unshrinking, unblanching, unapprehensive, confident, self-reliant, bold as a lion, bold as brass, enterprising, adventurous, venturous, venturesome, dashing, chivalrous, soldierly, heroic, fierce, savage, pugnacious, strong-minded, hardy, doughty, firm, determined, dogged, indomitable, up to, up to the scratch, upon one's mettle, reassured, unfeared, undreaded, one's blood being up, courage sans peur, fortes fortuna adjuvat, have I not in my time heard lions roar, I dare do all that may become a man, male vincetis sed vincite, omne solum forti patria, self-trust is the essence of heroism, stimulos dedit oemula virtus, strong and great, a hero, teloque animus proestantior omni, there, is always safety in valor, virtus ariete fortier.
N interiority, inside, interior, interspace, subsoil, substratum, intrados, contents, substance, pith, marrow, backbone, heart, bosom, breast, abdomen, vitals, viscera, entrails, bowels, belly, intestines, guts, chitterings, womb, lap, penetralia, recesses, innermost recesses, cave, interior, internal, inner, inside, inward, intraregarding, inmost, innermost, deep seated, gut, intestine, intestinal, inland, subcutaneous, abdominal, coeliac, endomorphic, interstitial, inwrought, inclosed, home, domestic, indoor, intramural, vernacular, endemic, internally, inwards, within, in, inly, here in, there in, where in, ab intra, withinside, in doors, within doors, at home, in the bosom of one's family.