The change from a liquid to a thickened, curdlike,
   insoluble state, not by evaporation, but by some kind of chemical
   reaction; as, the spontaneous coagulation of freshly drawn blood; the
   coagulation of milk by rennet, or acid, and the coagulation of egg
   albumin by heat. Coagulation is generally the change of an albuminous
   body into an insoluble modification.