Source : Webster's Revised Unabridged Dictionary (1913)

Upheaval \Up*heav"al\, n.
   The act of upheaving, or the state of being upheaved; esp.,
   an elevation of a portion of the earth's crust. --Lubbock.

Source : WordNet®

upheaval
     n 1: a state of violent disturbance and disorder (as in politics
          or social conditions generally); "the industrial
          revolution was a period of great turbulence" [syn: {turbulence},
           {Sturm und Drang}]
     2: a violent disturbance; "the convulsions of the stock market"
        [syn: {convulsion}, {turmoil}]
     3: (geology) a rise of land to a higher elevation (as in the
        process of mountain building) [syn: {uplift}, {upthrow}, {upthrust}]
     4: disturbance usually in protest [syn: {agitation}, {excitement},
         {turmoil}, {hullabaloo}]