Don't get confused | HUMPER and WHIRLER

A humper is a fault on pottery flatware. It appears as a domed base, causing the plate (or other flatware) to bow upwards. It looks ugly and causes gravy to accumulate in a ring around the edge of the plate. Regarded as seconds, or if its really bad, lump. On the other hand, a whirler is the exact opposite. It's also a pottery flatware fault, but this time refers to a plate with a bowed base so that it doesn't sit flat on a table but spins or whirls around. Giddy making.  Causes gravy to accumulate in a pool in the middle of the plate. More here>