Not healthy; somewhat affected with disease; or habitually indisposed; as a sickly person, or a sickly constitution; a sickly plant.

Producing disease extensively; marked with sickness; as a sickly time; a sickly autumn.

Tending to produce disease; as a sickly climate.

Faint; weak; languid. The moon grows sickly at the sight of day.

To make diseased.