Aqua-Lung
noun [ C ] trademark uk/ˈæk.wə.lʌŋ/ us/ˈæk.wə.lʌŋ/
（潜水者背负的）水肺，水中呼吸器
a brand name for a container of air that you carry on your back while swimming under the surface of the water, with a tube taking air to your mouth or nose to allow you to breathe