in‧su‧la‧tion /ˌɪnsjəˈleɪʃən, ˌɪnsjʊˈleɪʃən $ ˌɪnsə-/ noun [uncountable]

1. when something is insulated or someone insulates something:
Good insulation can save you money on heating bills.

2. material used to insulate something, especially a building:
glass-fibre insulation

[TahlilGaran] Dictionary of Contemporary English ▲