RhymeZone: comparator definitions

Definitions of comparator:

noun: Any device for comparing a physical property of two objects, or an object with a standard.
noun: An electronic device that compares two voltages, currents or streams of data.
noun: (law) anything that serves comparison
noun: (computing) An application or program that compares prices, rates, tariffs of flights, smartphones, cars, etc.

(Definitions from Wiktionary)