Ef′flo‐res″cence (?), n. [F. efflorescence.] 1. (Bot.) Flowering, or state of flowering; the blooming of flowers; blowth.
2. (Med.) A redness of the skin; eruption, as in rash, measles, smallpox, scarlatina, etc.
3. (Chem.) (a) The formation of the whitish powder or crust on the surface of efflorescing bodies, as salts, etc. (b) The powder or crust thus formed.