Wiktionary
n. A blanket made of a plastic material covered with a reflective metal agent; designed to reduce heat loss from a person's body following trauma
Wikipedia
A space blanket (also known as a Mylar blanket, first aid blanket, safety blanket, thermal blanket or weather blanket) is an especially low-weight, low-bulk blanket made of heat-reflective thin plastic sheeting. Their design reduces the heat loss in a person's body which would otherwise occur due to thermal radiation, water evaporation, or convection. Their compact size before unfurling and light weight makes them ideal when space is at a premium. They may be included in first aid kits and also in camping equipment. Lost campers and hikers have an additional possible benefit: the metallic surface appearance flashes in the sun, allowing use as an improvised distress beacon for searchers.
Usage examples of "space blanket".
She wrapped herself in a Mylar space blanket near the fire and pillowed her head on her flight jacket.
I would take a set of lightweight GoreTex, however, and everybody else took their poncho liner or space blanket.
I couldnt see Julia clearly on the stretcher, she was strapped down, covered in a silver space blanket.
He covered the Professor with a green foil space blanket to keep him warm, and then wrapped the stretcher straps around the whole setup.
A space blanket, silver on one side, black on the other, in her flight suit.