English Reference
noun

indicator

n.
US /ˈɪndəˌkeɪtɝ/ UK /ˈɪndɪkˌeɪtɐ/ in·di·ca·tor UK spelling indicator's, indicator's

  1. 01 B2 Upper Intermediate

    a sign or piece of information that shows the state or level of something.

    a sign or signal that points to a particular condition or level.

    Simple

    High house prices are often a good indicator of a strong local economy.

    In context

    The sudden drop in consumer spending served as a clear indicator that the public was becoming wary of future inflation.

  2. 02 C1 Advanced Academic Economics

    a statistic, like the unemployment rate, used to judge how well a country is doing.

    a statistical value used to measure the current state of an economy or to predict future trends.

    Simple

    The government looks at several economic indicators before changing interest rates.

    In context

    Leading economic indicators suggest that the manufacturing sector is poised for a significant recovery in the coming fiscal quarter.

  3. 03 B1 Intermediate British English

    the flashing light on a car that shows which way you are going to turn.

    a flashing light on a vehicle used to signal an intended change in direction.

    Simple

    He forgot to use his indicator when he turned into the driveway.

    In context

    The driver failed to engage his right indicator before merging, nearly causing a collision with the motorcyclist in his blind spot.

    turn signalblinker
  4. 04 B2 Upper Intermediate Technical

    a dial, needle, or screen on a machine that shows a measurement.

    a gauge or instrument that displays a specific measurement or status.

    Simple

    The temperature indicator on the dashboard started to climb into the red zone.

    In context

    Engineers monitored the pressure indicator closely during the test to ensure the pipes did not exceed their safety limits.

  5. 05 C1 Advanced Technical Science

    a substance that changes colour to show if a liquid is an acid or a base.

    a substance that undergoes a visible change, such as a colour shift, to indicate the presence or concentration of a chemical.

    Simple

    Litmus paper is a common indicator used in school science labs.

    In context

    The chemist added a few drops of the indicator to the solution to determine its pH level through a distinct colour transition.

  6. 06 C1 Advanced AcademicTechnical Science

    a plant or animal that shows if an environment is healthy or polluted.

    an organism whose presence, absence, or health reflects the specific environmental conditions of its habitat.

    Simple

    Frogs are a good indicator of water quality because they are sensitive to pollution.

    In context

    The decline of certain lichen species served as a biological indicator of increasing atmospheric nitrogen levels in the forest.

    bioindicator

Usage good indicator · important indicator · key indicator

Tracking both alongside established climate indicators could help scientists determine how slow environmental changes affect human biology over periods of decades.

ScienceDaily· 15 Aug 2026

One indicator is improving: the contact-tracing rate has passed 85 per cent nationally for the first time.

UN News· 13 Aug 2026

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

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin indicō
Level C1 · Advanced
Frequency Frequent
Updated