indicator

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time
noun a signal for attracting attention
noun a device for showing the operating condition of some system

From Late Latin indicātor (“one who points out”), from Latin indicō (“point out”). By surface analysis, indicate + -or; see indicate.

It is called the Indicator. — Following the Equator: A Journey Around the World, Mark Twain
The dial had two indicators which were together. — Astounding Stories, August, 1931, Various
The needle on the airspeed indicator leaped violently. — The Sex Life of the Gods, M. E. (Michael E.) Knerr

index, index number, indicant

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