indicator
gb/ˈɪndɪkˌeɪtɚ/ us/ˈɪndɪkˌeɪtɚ/
B1
English
~ 5800
Senses
0 senses
Noun
B2
entity
1
Sign or measure of a condition
A sign, fact, or number that shows the level or situation of something.
Usage pattern:
an indicator of [something]
Common mistake:
Learners often confuse "indicator" and "indication". Use "indicator" mainly for a sign that can be used as a measure (often countable and systematic, e.g., "economic indicators"), and "indication" for a more general sign or hint. Learners also sometimes say "indicator for" instead of the more natural "indicator of".
Synonyms
sign (More general and everyday; does not always suggest measurement or data the way "indicator" often does.)
|
measure (Emphasizes a numeric or quantitative way of showing level or amount.)
|
signal (Often used when the indicator is something that points to a future event or change.)
Antonyms
irrelevance (Refers to something that gives no useful information about the situation, the opposite of an informative indicator.)
Collocations
key indicator
|reliable indicator
|economic indicators
|health indicators
|performance indicators
|strong indicator
Themes
business
|science
|statistics
|daily life
|core_vocabulary
Examples
- Rising rental prices are a clear indicator of strong demand in the city.
- The test scores are a good indicator of how much the students have learned.
- Unemployment data is a key indicator of the country’s economic health.
- Frequent delays can be an early indicator of deeper problems in the project.
- Customer satisfaction is often used as an indicator of long‑term success.
Learner examples
- High prices are an indicator of high demand.
- Your grade is an indicator of your progress in this class.
- The number of visitors is an important indicator for the museum.
- Blood pressure is an indicator of heart health.
- Sales numbers are an indicator of how the company is doing.
Noun
B2
entity
2
Display or gauge on a device
A light or small part on a machine that shows information, like level or condition.
Usage pattern:
an indicator on [a device]
Common mistake:
Learners sometimes use "indicator" for large screens or full information panels. In everyday English, "indicator" usually refers to small, simple elements (lights, symbols, needles) that show one piece of information, while a full screen is called a "display" or "monitor".
Synonyms
gauge (Often used for round displays with a needle that shows a level, such as on vehicles or machines.)
|
display (More general; can refer to any screen or visual output, not just a simple indicator.)
Antonyms
control (A control changes how a device works, while an indicator only shows information without changing it.)
Collocations
indicator light
|battery indicator
|fuel indicator
|level indicator
|pressure indicator
|dashboard indicator
Themes
technology
|engineering
|transportation
Examples
- The battery indicator on my phone is down to five percent.
- A red indicator light comes on when the engine overheats.
- The fuel indicator is broken, so we don’t know how much gas is left.
- Check the level indicator before starting the machine.
- The dashboard indicators lit up when he started the car.
Learner examples
- The red indicator light means there is a problem.
- The fuel indicator shows that the tank is almost empty.
- There is a small indicator on the screen that shows the Wi‑Fi signal.
- Look at the temperature indicator before using the oven.
- The level indicator tells you how much water is in the tank.
Noun
B1
entity
3
Vehicle light showing a turn
In British English, the light on a car that blinks to show you will turn.
Usage pattern:
put on/turn on [your] indicator[s]
Common mistake:
Learners sometimes call this light a "blinker" or "turn signal" in British contexts. In the UK, "indicator" is the normal term. In North America, "turn signal" or "blinker" is more common than "indicator" for this sense.
Synonyms
turn signal (The usual term in American English; the meaning is the same.)
Collocations
left indicator
|right indicator
|turn on your indicators
|indicator stalk
|faulty indicator
Themes
transportation
|daily life
Examples
- You should have used your indicator before changing lanes.
- His right indicator isn’t working, so other drivers can’t see when he turns.
- The car failed its test because one of the rear indicators was broken.
- She forgot to cancel her indicator after finishing the turn.
- He pushed the indicator stalk down to signal a left turn.
Learner examples
- Always use your indicator before you turn.
- The left indicator on my car is broken.
- Turn on your indicators when you leave the roundabout.
- The front indicator light is very dim.
- He turned without putting on his indicator.
Noun
technical
B2
entity
4
Chemical that shows a substance
A chemical that changes, usually in colour, to show if another substance is present or how strong it is.
Usage pattern:
an indicator in [a solution/experiment]
Common mistake:
Learners may confuse an "indicator" with any chemical in the experiment. An indicator is specifically the chemical that changes in a visible way to show something about the solution, such as its pH.
Synonyms
reagent (A broader chemistry term for any substance used to cause a reaction or test; not all reagents are indicators.)
Collocations
pH indicator
|acid-base indicator
|color indicator
|use an indicator
|litmus indicator
Themes
chemistry
|science
|education
Examples
- We added a few drops of indicator to the solution to see whether it was acidic.
- Phenolphthalein is a common indicator used in titrations.
- The indicator turned pink, showing that the endpoint had been reached.
- Litmus paper acts as an indicator of acidity or alkalinity.
- This indicator changes from yellow to blue at a pH of about 7.
Learner examples
- In this experiment, we use an indicator to show if the liquid is an acid.
- The indicator changes color when the solution is basic.
- Litmus is a simple indicator for acids and bases.
- The teacher added the indicator to the beaker.
- The color of the indicator tells us the pH value.
Noun
technical
C1
entity
5
Function that marks membership (0/1)
In mathematics, a function or number that is 1 if something is true and 0 if it is not true.
Usage pattern:
an indicator function/variable for [a set/event]
Common mistake:
Learners may think "indicator" here means a general sign, but in mathematics it has a very specific meaning: a 0/1 function or variable that marks membership or whether a condition holds.
Synonyms
dummy variable (Common in statistics and econometrics; often used for 0/1 variables in models, not always strictly a function.)
Collocations
indicator function
|indicator variable
|binary indicator
|indicator random variable
Themes
mathematics
|statistics
|computer science
|science
Examples
- Let I(A) be the indicator of the event A.
- We include an indicator variable for each treatment group in the regression.
- The indicator function takes value 1 if x is in the set and 0 otherwise.
- Each category is represented by an indicator in the model.
- Define an indicator for whether the customer made a purchase.
Learner examples
- In this formula, the indicator is 1 when the event happens.
- We add an indicator variable that is 1 for women and 0 for men.
- The indicator function is 0 when x is not in the set.
- Each group has its own indicator in the table.
- Use an indicator variable to show if a student passed the test.
Grammar
Dictionary form
indicator
IPA
GB/ˈɪndɪkˌeɪtɚ/
US/ˈɪndɪkˌeɪtɚ/
Syllables & stress
in - dic - at - or (4 syllables)
Stress on 1st syllable (in)
Word forms
Noun
- Base: indicator
- Plural: indicators
Word family
Forms
indicators
noun
Core family
indicate
verb B1
indication
noun B1
Related words
indicative
adjective
Expressions
economic indicator
1/ˌɛkənˈɑmɪk ˈɪndɪkˌeɪtɚ/
fixed phrase
Statistic showing economic health
A number or fact, like unemployment or inflation, that shows how a country’s economy is doing.
Examples
- Unemployment is a major economic indicator that affects government policy.
- Inflation and GDP growth are important economic indicators.
- Recent economic indicators suggest that the economy is slowing down.
indicator species
1/ˈɪndɪkˌeɪtɚ spˈiʃiz/
fixed phrase
technical
Species that shows environmental quality
A type of plant or animal that shows, by where or how it lives, what the environment is like, for example how clean the water or air is.
Examples
- Frogs are often used as an indicator species for freshwater ecosystem health.
- The decline of this lichen, an important indicator species, suggests rising air pollution.
- Scientists chose several indicator species to monitor changes in the forest.
key performance indicator
1/kˈi pɚfˈɔɹməns ˈɪndɪkˌeɪtɚ/
fixed phrase
technical
Main measure of progress toward goals
A number or measure that shows how well a company, team, or project is doing compared to its goals.
Examples
- Customer retention is one of our key performance indicators this year.
- The manager reviewed several key performance indicators to judge the project’s success.
- Revenue growth is a key performance indicator for the business.
lagging indicator
1/lˈæɡɪŋ ˈɪndɪkˌeɪtɚ/
fixed phrase
technical
Measure that follows a trend
A measure that usually moves up or down only after the economy or system has already changed.
Examples
- Unemployment is generally considered a lagging indicator of economic performance.
- Company profits are a lagging indicator compared to stock prices.
- They focused too much on lagging indicators and reacted to the crisis too late.
leading indicator
1/lˈidɪŋ ˈɪndɪkˌeɪtɚ/
fixed phrase
technical
Measure that changes before a trend
A measure that usually moves up or down before the whole economy or system does, and can help predict future changes.
Examples
- Housing starts are often seen as a leading indicator of economic activity.
- Consumer confidence is a key leading indicator for retail sales.
- Analysts watch several leading indicators to forecast a possible recession.
turn indicator
1/tˈɚn ˈɪndɪkˌeɪtɚ/
fixed phrase
Vehicle light for turning
The light on a car that blinks to show other drivers that you will turn.
Examples
- The front left turn indicator needs to be replaced.
- He switched on the turn indicator before pulling out to overtake.
- The mechanic found a loose wire in the rear turn indicator.