Buna rubber, also known as nitrile rubber, is a type of synthetic rubber that is widely used in various industrial applications. It is popularly known for its durability, flexibility, and resistance to oil and chemicals. There are several synonyms for buna rubber which are often used interchangeably. These include NBR rubber, acrylonitrile-butadiene rubber, and Nitrile-butadiene rubber. The term NBR stands for 'Nitrile Butadiene Rubber' and refers to the monomers used in the production of the rubber. Acrylonitrile-butadiene rubber is the same as NBR rubber and is used commonly in the automotive industry. Nitrile-butadiene rubber is another synonym which refers to the same type of synthetic rubber.