What does "efflorescence" mean?

Efflorescence: (Med.) A redness of the skin; eruption, as in rash, measles, smallpox, scarlatina, etc.

Additional senses

  1. 2.(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.

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