Source : Webster's Revised Unabridged Dictionary (1913)

Inspissation \In`spis*sa"tion\, n.
   The act or the process of inspissating, or thickening a fluid
   substance, as by evaporation; also, the state of being so
   thickened.

Source : WordNet®

inspissation
     n 1: the process of thickening by dehydration
     2: the act of thickening [syn: {thickening}]