Unsound — Meaning, Definition & Synonyms

Unsound (adjective) — Senses, Synonyms & Antonyms

1. temporarily suffering from a disorder of the body

   "an unsound horse that will have to be disqualified from the race"

   similar: ailing, bad, down, ill, indisposed, peaked, peaky, poorly, punk, run-down, sick, sickened, unhealthy, unwell, out of sorts, under the weather
   related: symptomatic, cruddy, lousy, seedy, sickish, nauseated, nauseous, qualmish, queasy, squeamish, airsick, carsick, seasick, dizzy, light-headed, shaky, woozy, achy, feverish, diseased, disordered, decrepit, feeble, fragile, frail, infirm, invalid, sickly, weak, weakly, afflicted, troubled, debilitated, disabled, incapacitated, hypochondriac, hypochondriacal
   opposite: hale, healthful, healthy, sound, well, whole, wholesome
   near: able-bodied, conditioned, fit, well-conditioned, cured, better, convalescing, improved, mending, recovering, recuperating, rehabilitated, hardy, hearty, lusty, robust, rugged, stalwart, strong, tough, blooming, bouncing, chipper, flourishing, flush, thriving

2. not using or following good reasoning

   "it is clearly unsound to argue that just because a scientific explanation for that phenomenon does not currently exist, no such explanation is possible"

   similar: fallacious, illegitimate, illogical, inconsequent, inconsequential, invalid, irrational, nonrational, unreasonable, unreasoning, weak
   related: eristic, misleading, sophistic, specious, half-baked, ill-advised, misguided, unconsidered, unreasoned, inconsistent, absurd, asinine, foolish, meaningless, nonsensical, preposterous, reasonless, senseless, silly, Kafkaesque, odd, peculiar, strange, surreal, unusual, weird, insane, mad, nutty, wacky, disordered, disorganized, rambling, random, unconvincing, inexplicable, unaccountable, unexplainable
   opposite: logical, rational, reasonable, sound, valid, well-founded, well-grounded
   near: commonsense, sane, sensible, sober, wise, enlightened, informed, just, justified, reasoned, ordered, organized, clear, cogent, compelling, convincing, credible, persuasive, plausible, satisfying, solid, certain, sure, true, confirmed, corroborated, demonstrated, established, substantiated, validated

3. unable to think in a clear or sensible way

   "disgruntled relatives tried to prove that the woman was of unsound mind when she made her will"

   similar: bats, batty, bonkers (informal + sometimes offensive), brainsick, certifiable (dated, informal + disparaging), cracked (informal + disparaging), crackers (informal + disparaging), crazed (sometimes offensive), crazy (usually offensive), daft (chiefly British, informal), demented, deranged (often offensive), haywire, insane, loco (slang), mad, maniacal, mental (sometimes offensive), non compos mentis, nuts (informal + sometimes offensive), nutty (sometimes offensive), psycho (informal + disparaging), psychotic (sometimes offensive), unbalanced, unhinged, wud (chiefly Scottish), around the bend, off one's gourd, off one's head, off one's rocker, out of one's head, out to lunch (slang)
   related: dotty, fey, loopy, off, potty (chiefly British), teched, touched, aberrant, delirious, delusional, delusionary, disordered, disturbed, eccentric, odd, oddball, pixilated, queer, strange, foolish, senseless, witless, irrational, unreasonable, amok, ape, ballistic, bananas, berserk, nuclear, depressed, distracted, distraught, frantic, frenzied, hysterical, raving, wigged-out, fixated, monomaniac, monomaniacal, obsessed
   opposite: balanced, compos mentis, sane, sound, uncrazy
   near: clear, lucid, rational, reasonable, judicious, sensible, wise, healthy, normal, well-adjusted, unneurotic

4. not being in agreement with what is true

   "an unsound and pernicious stereotype"

   similar: erroneous, false, inaccurate, incorrect, inexact, invalid, off, untrue, untruthful, wrong, off base
   related: counterfactual, specious, spurious, deceptive, delusive, delusory, distorted, fallacious, fictitious, illusory, misleading, amiss, askew, awry, deceitful, dishonest, fraudulent, lying, mendacious, unconfirmed, unproven, untested, fabricated, invented, made-up, trumped-up
   opposite: accurate, correct, errorless, exact, factual, precise, proper, right, sound, true, valid, veracious
   near: confirmed, demonstrated, established, proven, tested, faultless, flawless, impeccable, letter-perfect, perfect