1. Contrary to good, in a physical sense; contrary or opposed to advantage, happiness, etc.; bad; evil; unfortunate; disagreeable; unfavorable.
Neither is it ill air only that maketh an ill seat, but ill ways, ill markets, and ill neighbors. (Bacon) There 's some ill planet reigns. (Shak)
2. Contrary to good, in a moral sense; evil; wicked; wrong; iniquitious; naughtly; bad; improper. Of his own body he was ill, and gave The clergy ill example. (Shak)
3. Sick; indisposed; unwell; diseased; disordered; as, ill of a fever. Whatever annoys or impairs happiness, or prevents success; evil of any kind; misfortune; calamity; disease; pain; as, the ills of humanity.
Synonym: bad, evil, wrong, wicked, sick, unwell.
Origin: ill, ille, Icel. Illr; akin to Sw. Illa, adv, dan. Ilde, adv.