Whole cumin seeds have a tangy, musky aroma and a savory, almost charred, flavor. They are brown-yellow in color and crescent-shaped. Like other schizocarp (dry fruit) spices, cumin seeds have ridges separated by oil-filled canals running along their lengths.
Whole cumin gains a lot when crushed and lightly toasted in a dry panthis releases a nuttier flavor with notes of roasted meats and vegetables. In fact, cumin is a favorite spice for emulating savory meat flavors in vegetarian cuisines. It should be used sparingly as it can overpower a dish easily.
Cumin is famously used in Turkish gyros (aka doner kebab) which are made with beef or lamb, versus traditional Greek gyro recipes that can call for chicken or lamb. In Indian cooking whole cumin is often fried in oil at the beginning of curry recipes. It is also found in Mexican dishes, and is ground and used in chili powder blends.