regulator

1. A device that controls or limits something.
2. A person or group that sets standards of practice, especially regulatory law as sanctioned by statutory law.
3. A very accurate clock, used by clockmakers to measure the timekeeping of each newly made clock.
4. A gene involved in controlling the expression of one or more other genes.
5. A device that controls the supply of steam to the cylinders of a steam locomotive.
6. Synonym of bulldozer (“member of intimidating group of white US Southerners”).
7. A positive real number determining the density of the units in Dirichlet's unit theorem.

Plural regulators