A vat is a large container, usually shaped like a barrel or tub, used for holding liquids during industrial processes. Picture a giant wooden barrel big enough to hold hundreds of gallons: that's a vat.

Vats have been important in manufacturing for centuries. Winemakers ferment grape juice in vats, cheesemakers age cheese in vats, and dyers used to color fabrics by soaking them in vats filled with dye. In a chocolate factory, you might see enormous vats where melted chocolate gets mixed and stirred. Breweries use copper or steel vats to make beer.

The word creates a specific image: something much bigger than a pot or bucket, industrial rather than household-sized. When a recipe calls for mixing ingredients in a vat, you know you're making enough to feed hundreds of people. You might read about vat-dyed fabrics in history books, referring to cloth colored using the traditional vat method, which produced especially rich, long-lasting colors.