unsound synonym | Thesaurus.com

Main Entry:	unsound
Part of Speech:	adjective
Definition:	not well; flimsy
Synonyms:	ailing, crazed, dangerous, decrepit, defective, delicate, demented, deranged, diseased, erroneous, fallacious, false, faulty, fragile, frail, ill, illogical, inaccurate, incongruous, incorrect, infirm, insane, insecure, insubstantial, invalid, lunatic, mad, rickety, shaky, specious, unbalanced, unhealthy, unhinged, unreliable, unsafe, unstable, unsteady, unsubstantial, unwell, weak, wobbly, flawed, in poor health, not solid, tottering, unbacked
Antonyms:	safe, sound, stable, strong, well

Main Entry:	chancy
Part of Speech:	adjective
Definition:	dangerous, risky
Synonyms:	capricious, contingent, dicey, erratic, fluky, hazardous, iffy*, incalculable, precarious, problematic, rocky, speculative, ticklish, touchy, tricky, uncertain, unpredictable, unsound, whimsical, fluctuant, problematical
Antonyms:	certain, safe, secure, sure, tried, not dangerous

* = informal/non-formal usage

Main Entry:	daft
Part of Speech:	adjective
Definition:	stupid; crazy
Synonyms:	absurd, asinine, bedlamite, bonkers, cracked, crackers, daffy, demented, deranged, dopey, flaky, foolish, fried, giddy, half-baked, idiotic, in the ozone, inane, insane, lunatic, mad, mental, nuts, nutty, off the wall, out of one's gourd, ridiculous, screwy, silly, simple, touched, unbalanced, unhinged, unsound, wacky, whacko, witless
Antonyms:	brainy, bright, intelligent, smart, understanding

* = informal/non-formal usage

Main Entry:	damaged
Part of Speech:	adjective
Definition:	broken, not working
Synonyms:	bent, down, gone, hurt, impaired, imperfect, injured, kaput, on the blink, on the fritz, run-down, shot, spoiled, unsound, beat-up, blemished, busted, dinged, flawed, flubbed, fouled up, glitched, in need of repair, in poor condition, in smithereens, loused up, marred, messed up, mucked up, no go, out of action, out of kilter, out of whack, screwed up, snafued, sunk, totaled
Antonyms:	fixed, mended, perfect, repaired, unbroken, undamaged, working, ok

* = informal/non-formal usage

Main Entry:	decrepit
Part of Speech:	adjective
Definition:	deteriorated, debilitated, especially as a result of age
Synonyms:	aged, antiquated, bedraggled, broken-down, crippled, dilapidated, doddering, effete, feeble, flimsy, fragile, frail, haggard, incapacitated, infirm, insubstantial, old, ramshackle, rickety, run-down, seedy, senile, shabby, shaking, superannuated, tacky, threadbare, tired, unsound, used, wasted, weak, weather-beaten, worn, worn-out, anile, battered, creaky, quavering, tottering, tumble-down, weakly
Antonyms:	fit, healthy, young

Main Entry:	defective
Part of Speech:	adjective
Definition:	broken, not working
Synonyms:	abnormal, amiss, damaged, deficient, faulty, impaired, imperfect, inadequate, incomplete, injured, insufficient, lacking, out of order, poor, sick, unfinished, unhealthy, unsound, wanting, blemished, flawed, on the bum, seconds, subnormal
Notes:	defective means having a defect or fault, while deficient means inadequate or lacking in amount or degree
Antonyms:	excellent, faultless, flawless, perfect, unbroken

Main Entry:	demented
Part of Speech:	adjective
Definition:	crazy, insane
Synonyms:	bananas, bemused, crackbrained, daft, delirious, deranged, distracted, distraught, flipped out, foolish, frenzied, fruity, hysterical, idiotic, in the ozone, lunatic, mad, maniac, maniacal, manic, non compos mentis, nutty as a fruitcake, out of one's gourd, out of one's tree, psycho, psychopathic, psychotic, schitzy, schizoid, unbalanced, unglued, unhinged*, unsound, whacko
Antonyms:	balanced, rational, reasonable, sane, sensible

* = informal/non-formal usage

Main Entry:	deranged
Part of Speech:	adjective
Definition:	crazy, insane
Synonyms:	ape, baked, berserk, cracked, crazed, delirious, demented, disconcerted, disordered, displaced, distracted, dotty, frantic, frenzied, fried, irrational, lunatic, mad, maniac, maniacal, nuts, perplexed, unbalanced, unhinged*, unsettled, unsound, bananas, disarranged, flipped, flipped out, loco, maddened, schizzo, unglued, unscrewed, unzipped, whacko
Antonyms:	balanced, calm, sane, ok

* = informal/non-formal usage

Main Entry:	diseased
Part of Speech:	adjective
Definition:	unhealthy
Synonyms:	afflicted, ailing, indisposed, infectious, infirm, rotten, sick, sickly, tainted, unsound, unwell, unwholesome, infected
Antonyms:	fit, healthy

Main Entry:	erroneous
Part of Speech:	adjective
Definition:	wrong, incorrect
Synonyms:	amiss, askew, awry, defective, fallacious, false, faulty, inaccurate, inexact, invalid, misguided, mistaken, off, specious, spurious, unfounded, unsound, untrue, all off, all wet, flawed, way off, wrong number
Antonyms:	correct, right, true, valid

Main Entry:	fallacious
Part of Speech:	adjective
Definition:	false, wrong
Synonyms:	deceptive, delusive, erroneous, fictitious, fishy, fraudulent, illogical, illusory, incorrect, invalid, irrational, mad, misleading, mistaken, off, phony, spurious, unfounded, unreal, unreasonable, unsound, untrue, beguiling, deceiving, deluding, delusory, reasonless, sophistic, sophistical, ungrounded, unreasoned, way off
Antonyms:	correct, real, true, truthful

* = informal/non-formal usage

Main Entry:	faulty
Part of Speech:	adjective
Definition:	not working; incorrect
Synonyms:	adulterated, amiss, awry, bad, below par, blamable, broken, cracked, damaged, debased, defective, deficient, distorted, erroneous, fallacious, fallible, false, frail, impaired, imperfect, inaccurate, inadequate, incomplete, inexact, injured, insufficient, invalid, lame, leaky, lemon, maimed, malformed, out of order, rank, sick, tainted, unfit, unreliable, unsound, weak, wrong, blemished, botched, flawed, imprecise, malfunctioning, marred, unretentive, warped
Antonyms:	accurate, correct, perfect, sound, strong, working

Main Entry:	fragile
Part of Speech:	adjective
Definition:	breakable, dainty
Synonyms:	brittle, crisp, crumbly, decrepit, delicate, feeble, fine, flimsy, frail, friable, infirm, insubstantial, slight, unsound, weak, fracturable, frangible, shatterable, shivery, weakly
Antonyms:	durable, firm, strong, tough, unbreakable

Main Entry:	frail
Part of Speech:	adjective
Definition:	breakable, weak
Synonyms:	brittle, dainty, decrepit, delicate, feeble, fishy, flimsy, fragile, infirm, insubstantial, puny, sad, sickly, slender, slight, slim, tender, tenuous, thin, unsound, unsubstantial, vulnerable, wishy-washy*, wispy, fracturable, frangible, shatterable, shattery, wimpy
Antonyms:	firm, strong, unbreakable

* = informal/non-formal usage

Main Entry:	hazardous
Part of Speech:	adjective
Definition:	dangerous, unpredictable
Synonyms:	chancy, dicey, difficult, hairy, haphazard, hot*, insecure, perilous, precarious, risky, touchy, uncertain, unhealthy, unsafe, unsound, venturesome, wicked, parlous
Antonyms:	certain, guarded, predictable, protected, safe, secure

* = informal/non-formal usage

Main Entry:	illogical
Part of Speech:	adjective
Definition:	not making sense
Synonyms:	absurd, cockeyed, fallacious, false, fatuous, faulty, groundless, hollow, implausible, inconclusive, incongruous, inconsistent, incorrect, invalid, irrational, irrelevant, mad, meaningless, nutty, off the wall, preposterous, screwy*, senseless, specious, spurious, unconnected, unreasonable, unscientific, unsound, unsubstantial, untenable, wacky, casuistic, inconsequent, not following, self-contradictory, sophistic, sophistical, unproved, without basis, without foundation
Antonyms:	correct, logical, meaningful, rational, reasonable, right, sensible

* = informal/non-formal usage

Main Entry:	impaired
Part of Speech:	adjective
Definition:	injured, faulty
Synonyms:	broken, damaged, debilitated, defective, down, harmed, hurt, imperfect, kaput, on the blink*, on the fritz, spoiled, unsound, busted, flawed, marred
Antonyms:	healthy, perfect, strong

* = informal/non-formal usage

Main Entry:	imperfect
Part of Speech:	adjective
Definition:	flawed
Synonyms:	amiss, below par, broken, damaged, defective, deficient, dud, faulty, garbage, immature, impaired, incomplete, inexact, injured, junk, lemon, limited, low, minus, partial, patchy, rudimentary, sick, sketchy, two-bit*, undeveloped, unfinished, unsound, vicious, bottom-of-barrel, disfigured, few bugs, marred, schlocky, warped
Antonyms:	excellent, faultless, finished, perfect, pure, unblemished, unflawed

* = informal/non-formal usage

Main Entry:	inaccurate
Part of Speech:	adjective
Definition:	erroneous
Synonyms:	all wet, careless, counterfactual, defective, discrepant, doesn't wash, fallacious, false, faulty, imprecise, in error, incorrect, inexact, mistaken, off, off base, out, specious, unfaithful, unreliable, unsound, untrue, way-off, wide, wild, wrong
Antonyms:	accurate, correct, right

* = informal/non-formal usage

Main Entry:	incorrect
Part of Speech:	adjective
Definition:	wrong
Synonyms:	erroneous, false, faulty, improper, inaccurate, inappropriate, inexact, mistaken, out, specious, unreliable, unseemly, unsound, unsuitable, untrue, wide of the mark, counterfactual, flawed, imprecise, not trustworthy, unfitting, way off, wrong number
Antonyms:	correct, right, true