(transitive) To reduce in size, force, value, amount, or degree.

(transitive) To make thinner, as by physically reshaping, starving, or decaying.

(intransitive) To become thin or fine; to grow less.

(transitive) To weaken.

(transitive) To rarefy.

(transitive, medicine) To reduce the virulence of a bacterium or virus.

(transitive, electronics) To reduce the amplitude of an electrical, radio, or optical signal.

(of a beer) (brewing) To become less dense as a result of the conversion of sugar to alcohol.

(botany, of leaves) Gradually tapering into a petiole-like extension toward the base.