The kidneys are a pair of organs on either side of the spine in the lower abdomen. Each kidney is about the size of a fist. Attached to the top of each kidney is an adrenal gland. A mass of fatty tissue and an outer layer of fibrous tissue (Gerota's fascia) enclose the kidneys and adrenal glands.
A roll of duct tape. A roll of duct tape. The definition of a roll is something that's been coiled or twisted into a cylinder. An example of a roll is duct tape.
A roll cage is a specially-constructed tubular frame built in or around the cab of a vehicle to protect its occupants from injury in the case of an accident or rollover. A standard feature in race cars and stunt cars, roll cages are made of steel tubing and include a geometric design to enhance stability and strength.