Turmeric is a plant that's related to ginger and is commonly used in cooking. The turmeric used as a spice is made by grinding and drying the root of the turmeric plant.
When a recipe calls for ground turmeric, you'll reach for a bright yellow powder with a mustard-like smell. Turmeric adds this hue to the dishes it's included in, as well as a slightly bitter flavor. It's used in a wide variety of dishes world-wide, although it's particularly common in South and East Asian foods like Indian curries, Vietnamese bánh xèo, and Thai turmeric soup. Some experts believe turmeric comes from the Medieval Latin terra merita, or "worthy earth."