indicator

/'indikeitə/
Học thuật
Thân thiện
indicator

A student adds a chemical indicator to a clear solution in a beaker.

Definition
  1. Noun:
    • A substance that changes color to show the presence of a specific ion or substance: In chemistry, an "indicator" is a compound used to signal, typically through a color change, the completion of a reaction or the presence of a particular condition, such as acidity.
    • A device that shows the operating condition of a system: In mechanics or technology, an "indicator" is a gauge, light, or dial that displays information about the state or performance of a machine or system.
    • A signal for attracting attention: An "indicator" can be something that serves as a sign or signal to draw notice to a specific thing or situation.
    • A number or ratio derived from observed facts that reveals relative changes over time: In statistics, economics, or research, an "indicator" is a measurable value used to represent or track trends, performance, or conditions.
Usage Examples
  • Noun (Chemical Substance):
    • Litmus paper is a common acid-base indicator.
    • The scientist added a few drops of the indicator to the solution.
  • Noun (Device):
    • The fuel indicator on the dashboard was showing empty.
    • Check the temperature indicator to see if the engine is overheating.
  • Noun (Signal):
    • The sudden drop in sales is a clear indicator of economic trouble.
    • Her smile was a good indicator of her approval.
  • Noun (Statistical Measure):
    • The unemployment rate is a key economic indicator.
    • They monitor several health indicators to assess the population's well-being.
Advanced Usage
  • Leading indicator: A measurable factor that changes before the economy or a market begins to follow a particular pattern or trend.
    • Consumer confidence is often considered a leading indicator of economic health.
  • Indicator species: In biology and ecology, a species whose presence, absence, or abundance reflects a specific environmental condition.
    • The health of coral reefs is an indicator species for ocean water quality.
Variants and Related Words
  • Indicate (verb): To point out, show, or suggest something.
    • The data indicates a positive trend.
  • Indicative (adjective): Serving as a sign or indication of something.
    • His tone was indicative of his frustration.
  • Indicator light (noun phrase): A small light on a device or vehicle that shows a specific status.
    • The indicator light flashes when the battery is low.
Synonyms
  • Gauge: A device for measuring or testing something.
  • Signal: A gesture, action, or sound conveying information or an instruction.
  • Measure: A standard unit used to express size, amount, or degree.
  • Sign: An object, quality, or event whose presence indicates the probable occurrence of something else.
Related Phrases
  • Turn indicator: (Also "turn signal") A flashing light on a vehicle showing the direction in which it is about to turn.
    • Always use your turn indicator before changing lanes.
  • Performance indicator: A measurable value that demonstrates how effectively a company or project is achieving key objectives.
    • Customer satisfaction is our most important performance indicator.
Related Idioms
  • A sure indicator: Something that is a definite or reliable sign of a particular condition or outcome.
    • A sudden silence in the room is a sure indicator that something is wrong.
indicator

A student adds a chemical indicator to a clear solution in a beaker.

Noun
  1. (chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction
  2. a device for showing the operating condition of some system
  3. a signal for attracting attention
  4. 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