- To blossom forth. - 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. - To become covered with a whitish crust or light
crystallization, from a slow chemical change between some of the
ingredients of the matter covered and an acid proceeding commonly from
an external source; as, the walls of limestone caverns sometimes
effloresce with nitrate of calcium in consequence of the action in
consequence of nitric acid formed in the atmosphere.