insulation

Short definition from Wiktionary

Noun

1. 1
   The act of insulating; detachment from other objects; isolation.
2. 2
   The state of being insulated; detachment from other objects; isolation.
3. 3
   Any of a variety of materials designed to reduce the flow of heat, either from or into a building.
4. 4
   The act of separating a body from others by nonconductors, so as to prevent the transfer of electricity, heat, or sound
5. 5
   The state of a body so separated.
6. 6
   a medium in which it is possible to maintain an electrical field with little supply of energy from additional sources.