Source : Webster's Revised Unabridged Dictionary (1913)

Invertible \In*vert"i*ble\, a. [From {Invert}.]
   1. Capable of being inverted or turned.

   2. (Chem.) Capable of being changed or converted; as,
      invertible sugar.

Invertible \In*vert"i*ble\, a. [Pref. in- not + L. vertere to
   turn + -ible.]
   Incapable of being turned or changed.

         An indurate and invertible conscience.   --Cranmer.

Source : WordNet®

invertible
     adj : having an additive or multiplicative inverse [ant: {non-invertible}]