Synonyms for Unhealthy:

adj.

dangerous (adjective)
shaky.
diseased (adjective)
Inflicted, decrepit, ailing, affected, sickly, cursed, nauseous, ill, infected, diseased, pestilent, disabled, infirm, handicapped, sick, indisposed.
harmful (adjective)
detrimental, harmful, injurious, damaging, baleful, bad, unwholesome, deleterious.
rancid (adjective)
carious.
sick (adjective)
diseased, feeble, ailing, ill, weak, delicate, frail, sickly, shaky, debilitated, invalid, unsound, infirm.
sickly (adjective)
delicate.
unhealthful (adjective)
unwholesome.
unhealthy (adjective)
insalubrious, unwholesome, infected, noxious, deadly, contagious, diseased, pathological, contaminated, unsanitary, malignant, unhygienic, pestilent, septic, gangrenous, toxic, poisonous.
very bad in effect on well-being (adjective)
villainous, demoralizing, degenerate, corrupt, unwholesome, deleterious, rotten, morbid, perverse, harmful, unhealthful, detrimental, poisonous, insalubrious, unsanitary, noxious.

adv

sickly (adverb)
rickety, shaky, undernourished, feeble, delicate, Spindling, weak, invalid.

n.

frail, fragile, infectious, worse, failing. health, unsalutary, debilitating. dull, nonprofit, contaminative, uneconomic, underfunded, demoralizing, right, loss-making, untapped, corruptive, unprofitable, not-for-profit, uneconomical. macabre. unhealthy (noun)
puffy, enfeebled, windburned, mortified, cankerous, debilitated, diseased, proinflammatory, membranous, rheumatic, creaky, dehydrated, blebby, ulcerous, morbid, tumid, raw, angry, inflamed, flatulent, membrane-forming, sunburnt, arthritic, gangrenous, gassy, enlarged, frothing, unfit, asthmatic, sallow, carbuncled, insalubrious, ingrowing, sore, swollen, foaming, bad, varicose, unhealthful, wheezing, sunburned, caseous, bloated, dropsical, rheumatoid, sore-eyed, wheezy, turgid, colicky, ingrown, unsound, carbuncular, tumescent, edematous, mental, pathologic, carious, sickly, infirm, puffed, bloodshot, yellow, windburnt, blistery, foamy, ulcerated, chilblained, seedy, Distended, pathological, inflammatory, jaundiced.

Other synonyms:

feeble, underfunded, unsalutary, frail, debilitating, contaminative, worse, shaky, corruptive, unprofitable, flagitious, unfit, loss-making, uneconomic, demoralizing, uneconomical, undernourished. depraved, fragile, miscreant, macabre, villainous, corrupt. failing, perverse. degenerate. rotten. dull. distended
Distended.

Usage examples for unhealthy

  1. Their faults are the outcome of superstition, slavery to custom, and an unhealthy climate. – Tales of Bengal by S. B. Banerjea
  2. Much could be said about the healthy appearance and happy life of the members of this Colony, but as they have not been brought from the unhealthy squalid misery of the city, this is not of so much interest. – The Social Work of the Salvation Army by Edwin Gifford Lamb
  3. After his midday meal, he came into the habit of taking long tramps through the streets of the poorer quarters, resting himself in little traktirs, finding unhealthy companionship in the patent discontent, poverty, and misery of the laboring class. – The Genius by Margaret Horton Potter