Other forms: insulators
An insulator is a material that will not let electricity pass through it. Rubber is an insulator, ceramic insulators, wrapped in an insulator.
The opposite is a conductor, and semiconductors sit between them — which is the whole basis of electronics. Glass, rubber, plastic and dry air are good electrical insulators, and the ceramic discs on overhead power lines are called insulators for exactly this reason. The word also covers materials that will not carry heat: fibreglass and foam insulate a loft. Note insulate and insulation, which in ordinary speech usually mean the heat kind.
Latin insula means an island, and to insulate is to make something into an island — cut off from everything around it. The metaphor is exact: an insulator surrounds a wire with a moat nothing can cross.
From insulate + or.
Etymology from Wiktionary, CC BY-SA
Practised in Science & Space