The term 'GIANT TUB' can be solved by the three letter word 'VAT'. A VAT is a large container, usually made of metal or wood, used for storing liquids or other substances. It is often used in industrial settings, such as breweries, wineries, and distilleries, to store and ferment large quantities of liquid. Vats are also commonly used in the production of food products, such as cheese, yogurt, and ice cream.