Conical burr
also: conical burrs
A burr set with a cone-shaped center spinning inside a ringed outer burr; efficient, cooler-running, common at home.
A conical burr set has a cone-shaped inner burr that spins inside a matching ringed outer burr. Beans fall into the top, get cracked, and travel down the widening gap until they are small enough to exit. It is one of the two common geometries in a burr grinder, the other being the flat burr.
Why it matters: conical burrs grind efficiently at lower motor speeds, so they run cooler and quieter and need less power. That makes them common in hand grinders and home electric grinders. They are forgiving and reliable for everyday brewing.
In the cup, conical burrs are often described as giving a slightly broader range of particle sizes than flats, which some tasters read as more body and a rounder profile, while flats can read as more clarity. The difference is real but subtle, and is easily swamped by your grind setting, dose, and technique. For most home setups, a well-made conical is more than enough.