(1):

(n.) To vitriolize.

(2):

(n.) To dip in dilute sulphuric acid; to pickle.

(3):

(n.) A sulphate of any one of certain metals, as copper, iron, zinc, cobalt. So called on account of the glassy appearance or luster.

(4):

(n.) Sulphuric acid; - called also oil of vitriol. So called because first made by the distillation of green vitriol. See Sulphuric acid, under Sulphuric.