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Indicator
WordNet
noun
(1) A device for showing the operating condition of some system
(2) 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
(3) A signal for attracting attention
(4) (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
WiktionaryText
Etymology
< < ; see indicate.
Noun
- a pointer or index that indicates something
- a meter or gauge
- the needle or dial on such a meter
- any of many substances, such as litmus, used to indicate the concentration of a substance, or the degree of a reaction
- a plant or animal whose presence is indicative of some specific environment
- a measure, such as unemployment rate, which can be used to predict economic trends
- a trafficator