To flog or beat with a knout.
A leather scourge (multi-tail whip), in the severe version known as 'great knout' with metal weights on each tongue, notoriously used in imperial Russia.
To beat with a ruler (as a traditional school punishment).
A person who rules or governs; someone or something that exercises dominion or controlling power over others.
A (usually rigid), flat, rectangular measuring or drawing device with graduations in units of measurement; a straightedge with markings.