surplus or excess, remainder
仂 centers on what is left over after a main portion is taken: a surplus, excess, or remainder.
仂 combines 亻 (person) and 力 (strength). The exact historical development is uncertain, but it likely expressed the idea of a person's strength producing a surplus or remainder.
A person 亻 with extra strength 力 has a surplus of energy—more than enough, leaving a remainder.
For ドウ, imagine a person with surplus strength doing doughnuts in a parking lot: dough -> ドウ, and the extra energy leaves a surplus.