regulator

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun any of various controls or devices for regulating or controlling fluid flow, pressure, temperature, etc.
noun an official responsible for control and supervision of a particular activity or area of public interest
noun a control that maintains a steady speed in a machine (as by controlling the supply of fuel)

From regulate + -or.

THE BOY SPIES WITH THE REGULATORS. — The Camp Fire Girls Solve a Mystery; Or, The Christmas Adventure at Carver House, Hildegard G. Frey
I mean that you didn’t invent this regulator. — Demian, Hermann Hesse
They consulted together, and the institution of Regulators was the result of their deliberations. — Western Characters; or, Types of Border Life in the Western States, John Ludlum McConnel

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