A dog clutch
is a type of clutch
that couples two rotating shafts or other rotating components not by friction
but by interference. The two parts of the clutch are designed such that one will push the other, causing both to rotate at the same speed and will never slip.
Dog clutches are used where slip is undesirable and/or the clutch is not used to control torque. Without slippage, dog clutches are not affected by wear in the same way that friction clutches are.