in·​di·​ca·​tor ˈin-də-ˌkā-tər How to pronounce indicator (audio)
: one that indicates: such as
: an index hand (as on a dial) : pointer
: an instrument for automatically making a diagram that indicates the pressure in and volume of the working fluid of an engine throughout the cycle
: any of a group of statistical values (such as level of employment) that taken together give an indication of the health of the economy
: a substance (such as litmus) used to show visually (as by change of color) the condition of a solution with respect to the presence of a particular material (such as a free acid or alkali)
: an organism or ecological community so strictly associated with particular environmental conditions that its presence is indicative of the existence of these conditions
indicatory adjective

Example Sentences

Economic indicators suggest that prices will go up. a control panel with various indicator lights
Recent Examples on the Web The price of bitcoin, generally seen as an indicator of the broader crypto market, declined dramatically from its late 2021 heights. Brian Cheung, NBC News, 18 Nov. 2022 The state doesn’t have a formal definition for recessions, but Lehner said forecasters are looking at employment declines as a key indicator. oregonlive, 16 Nov. 2022 In the absence of reliable, comprehensive testing results (with Covid-19, home test results are typically not reported to health authorities), epidemiologists focus on hospitalizations as an indicator of severe illness. Josh Zumbrun, WSJ, 11 Nov. 2022 The efficiency gap is useful as an indicator that pins down partisanship in voting districts. Manon Bischoff, Scientific American, 10 Nov. 2022 But by making verification available to all who are prepared to pay, Musk is also eroding the feature’s power as an indicator of reliability, many experts have warned. Time, 7 Nov. 2022 What’s next: Investors will next look to housing starts data next week as an indicator of where the housing market is headed. Nicole Goodkind, CNN, 17 Oct. 2022 Though scorpions may not be as well-loved as some other wildlife, their survival—or demise—can serve as an indicator of health and balance in desert ecosystems, which are home to a surprisingly high amount of plant and animal diversity. Sarah Kuta, Smithsonian Magazine, 26 Sep. 2022 As the drug war ramped up during the 1970s and 1980s, drug quantity and weight were conceived as an objective indicator of a person’s involvement in the drug trade. Zachary Siegel, The New Republic, 20 Sep. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'indicator.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1666, in the meaning defined at sense 1

Time Traveler
The first known use of indicator was in 1666

Dictionary Entries Near indicator

Cite this Entry

“Indicator.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2022.

Kids Definition



in·​di·​ca·​tor ˈin-də-ˌkāt-ər How to pronounce indicator (audio)
: one that indicates: as
: a pointer on a dial or scale
: a substance used to show visually (as by change of color) the presence of acid or base in a solution

Medical Definition



in·​di·​ca·​tor ˈin-də-ˌkāt-ər How to pronounce indicator (audio)
: a substance (as a dye) used to show visually (as by a change in color) the condition of a solution with respect to the presence of a particular material (as a free acid or alkali)
litmus and phenolphthalein are acid-base indicators

More from Merriam-Webster on indicator

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