Jacuzzi is a company that produces whirlpool bathtubs and spas. Its first product was a bath with massaging jets. The trademarked Jacuzzi name is commonly used to refer to any bath with water jets, and can thus be considered a generalized trademark. Sometimes spas and hot tubs are also referred to as Jacuzzi. The company advertises that "they are Jacuzzi, and everyone Else's are just hot tubs.
