Source : Webster's Revised Unabridged Dictionary (1913)

Insulation \In`su*la"tion\, n.
   1. The act of insulating, or the state of being insulated;
      detachment from other objects; isolation.

   2. (Elec. & Thermotics) The act of separating a body from
      others by nonconductors, so as to prevent the transfer of
      electricity or of heat; also, the state of a body so
      separated.

Insulation \In`su*la"tion\, n.
   The material or substance used in insulating.

Source : WordNet®

insulation
     n 1: the state of being isolated or detached; "the insulation of
          England was preserved by the English Channel" [syn: {insularity},
           {insularism}, {detachment}]
     2: a material that reduces or prevents the transmission of heat
        or sound or electricity [syn: {insulating material}, {insulant}]
     3: the act of protecting something by surrounding it with
        material that reduces or prevents the transmission of
        sound or heat or electricity