(1):

(v. t.) To make pure or clear from material defilement, admixture, or imperfection; to free from extraneous or noxious matter; as, to purify liquors or metals; to purify the blood; to purify the air.

(2):

(v. t.) Hence, in figurative uses: (a) To free from guilt or moral defilement; as, to purify the heart.

(3):

(v. t.) To free from ceremonial or legal defilement.

(4):

(v. t.) To free from improprieties or barbarisms; as, to purify a language.

(5):

(v. i.) To grow or become pure or clear.