Source : Webster's Revised Unabridged Dictionary (1913)

Efflorescence \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.

Source : WordNet®

efflorescence
     n 1: the period of greatest prosperity or productivity [syn: {flower},
           {prime}, {peak}, {heyday}, {bloom}, {blossom}, {flush}]
     2: any red eruption of the skin [syn: {rash}, {roseola}, {skin
        rash}]
     3: the time and process of budding and unfolding of blossoms
        [syn: {blossoming}, {flowering}, {florescence}, {inflorescence},
         {anthesis}]
     4: a powdery deposit on a surface [syn: {bloom}]