{{wiktionary|indicator}} '''Indicator''' may refer to:
{{TOC right}} == Biology == * Environmental indicator of environmental health (pressures, conditions and responses) * Ecological indicator of ecosystem health (ecological processes) * Health indicator, which is used to describe the health of a population * Honeyguides, also known as "indicator birds", a family of Old World tropical birds ** ''Indicator'' (genus), a genus of birds in the honeyguide family * Indicator species, a species that defines a characteristic of an environment * Indicator bacteria, bacteria used to detect and estimate the level of fecal contamination of water * Indicator organism, organisms used to measure such things as potential fecal contamination of environmental samples * Indicator plant, a plant that acts as a measure of environmental conditions * Indicator value, one of two terms in ecology referring to the classification of organisms * Iodine–starch test, a method to test for the presence of starch or iodine.
== Chemistry == * Complexometric indicator, a chemical detector for metal ions in complexometric titrations. * Humidity indicator card, a card impregnated with chemicals that change colour when a particular humidity is exceeded. * pH indicator, a chemical detector for protons in acid-base titrations. * Redox indicator, a chemical detector for redox titrations. * Zeta potential, a property of interfaces in fluids for Zeta potential titration.
== Economics == * Economic indicator * Macroeconomic indicators, economic indicators provided by agencies and bureaus of various government statistical organizations and sometimes by private organizations * Performance indicator * Technical indicator, a tool used in the technical analysis of financial securities
== Mathematics, engineering, and industry == * Indicator (distance amplifying instrument), any of various instruments used to accurately measure small distances, and amplify them to make them more obvious * Indicator (metadata), a Boolean value that may contain only the values true or false and includes the meaning of these values * Indicator (statistics), a concept in statistics, research design and social sciences * Indicator diagram, a graph of pressure against stroke within a piston engine * Indicator function of a subset of the domain, a concept in mathematics * Indicator light * Indicator net, nets anchored at various depths to the sea bed around Allied naval bases during World War II intended to entangle U-boat traffic of the enemy * Indicator of compromise, an artifact observed in computer forensics that indicates an intrusion
== Other uses == * ''Indicator'' (Deine Lakaien album), 2010 * ''Indicator'' (Onward to Olympas album), 2012 * Indicator Island, in the Argentine Islands of Antarctica * ''The Indicator'' (1819–1821), a weekly literary journal edited by Leigh Hunt * ''The Indicator'', a daily podcast produced by Planet Money * A synonym for the turn signal of an automobile
==See also== * Indicate/indication (disambiguation)
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