(v. i.) To change on the surface, or throughout, to a whitish, mealy, or crystalline powder, from a gradual decomposition, esp. from the loss of water, on simple exposure to the air; as, Glauber's salts, and many others, effloresce.
EFFLORESCE
Meaning of EFFLORESCE in English
Webster's English dictionary. Английский словарь Webster. 2012