1530s, "make into an island," from Late Latin insulatus "made like an island," from insula "island" (see isle). Sense of "place in an isolated situation, cause (someone or something) to be detached from surroundings" is from 1785. Electrical/chemical sense of "block from electricity or heat" (by interposition of a non-conductor) is from 1742. Related: Insulated; insulating.
We had his bedroom insulated before winter came
insufflation
insula
insular
insularism
insularity
insulate
insulation
insulator
insulin
insult
insulting