indicator

noun

in·​di·​ca·​tor ˈin-də-ˌkā-tər 

1

: one that indicates: such as

a

: an index hand (as on a dial) : pointer

b(1)

: gauge sense 2b, dial sense 1a

(2)

: an instrument for automatically making a diagram that indicates the pressure in and volume of the working fluid of an engine throughout the cycle

2

: any of a group of statistical values (such as level of employment) that taken together give an indication of the health of the economy

3

a

: 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)

b

: tracer sense 4b

4

: an organism or ecological community so strictly associated with particular environmental conditions that its presence is indicative of the existence of these conditions

indicatory

in-ˈdi-kə-ˌtȯr-ē 

adjective

Synonyms of indicator

• needle
• index

Examples of indicator in a Sentence

Economic indicators suggest that prices will go up.

a control panel with various indicator lights

Recent Examples on the Web

The inner workings are also dazzling, with the self-winding Caliber CH 28-520 C FUS offering a dual time zone display, flyback chronograph, day/night indicators, and a date display. —Rachel Cormack, Robb Report, 8 Nov. 2025

Finding short fragments of DNA less than 40 base pairs long is an initial positive indicator of older DNA, but other environmental factors might be at play, according to Elena Irene Zavala, an assistant professor in forensic genetics at the University of Copenhagen. —Katie Hunt, CNN Money, 7 Nov. 2025

Buchmann said that although the team is similarly looking forward to seeing precinct-level data to get a clearer picture of how Wyandotte County voted, the team found a few indicators leading up to the election that told them the race between Watson and Mulvany Henry would be close. —Kansas City Star, 7 Nov. 2025

McDaniel’s teams are minus-18 in turnover margin in three-and-a-half seasons, and McDaniel stresses that turnovers are the best indicators of who wins football games. —Omar Kelly november 7, Miami Herald, 7 Nov. 2025

Word History

First Known Use

1666, in the meaning defined at sense 1

Phrases Containing indicator

• plan position indicator

Rhymes for indicator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

Kids Definition

indicator

noun

in·​di·​ca·​tor ˈin-də-ˌkāt-ər 

1

: one that indicates: as

a

: a pointer on a dial or scale

b

: gauge entry 1 sense 2a

2

: a substance used to show visually (as by change of color) the presence of acid or base in a solution

Medical Definition

indicator

noun

in·​di·​ca·​tor ˈin-də-ˌkāt-ər 

: 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