indicator

View more Science videos

A substance used to show the presence of a chemical substance or ion by its colour. Acid-base indicators are compounds, such as phenolphthalein and methyl orange, that change colour reversibly, depending on whether the solution is acidic or basic. They are usually weak acids in which the un-ionized form HA has a different colour from the negative ion A⁻. In solution the indicator dissociates slightly

In acid solution the concentration of H⁺ is high, and the indicator is largely undissociated HA; in alkaline solutions the equilibrium is displaced to the right and A⁻ is formed. Useful acid-base indicators show a sharp colour change over a range of about 2 pH units. In titration, the point at which the reaction is complete is the equivalence point (i.e. the point at which equivalent quantities of acid and base are added). The end point is the point at which the indicator just changes colour. For accuracy, the two must be the same. During a titration the pH changes sharply close to the equivalence point, and the indicator used must change colour over the same range.

Other types of indicator can be used for other reactions. Starch, for example, is used in iodine titrations because of the deep blue complex it forms. Oxidation-reduction indicators are substances that show a reversible colour change between oxidized and reduced forms. See also adsorption indicator.

---

technical measurement securities market analysts use to forecast the market’s direction, such as investment advisory sentiment, volume of stock trading, direction of interest rates, and buying or selling by corporate insiders.

Previous:	Indication of Interest, Indication
Next:	Indirect Cost and Expense, Indirect Labor Costs

noun

Something visible or evident that gives grounds for believing in the existence or presence of something else: badge, evidence, index, indication, manifestation, mark, note, sign, signification, stamp, symptom, token, witness. See show/hide.

n. in intelligence usage, an item of information that reflects the intention or capability of a potential enemy to adopt or reject a course of action.

See the Introduction, Abbreviations and Pronunciation for further details.

Statistics used to measure current conditions as well as to forecast financial or economic trends. Indicators are used extensively in technical analysis to predict changes in stock trends or price patterns. In fundamental analysis, economic indicators that quantify current economic and industry conditions are used to provide insight into the future profitability potential of public companies.

Investopedia Says:
In the context of technical analysis, an indicator is a mathematical calculation based on a securities price and/or volume. The result is used to predict future prices. Common technical analysis indicators are the moving average convergence-divergence (MACD) indicator and the relative strength index (RSI).

In an economic context, an indicator could be a measure such as the unemployment rate, which can be used to predict future economic trends. Common general economic indicators are the unemployment rate, new housing starts and the consumer price index (CPI).

Related Links:
The economy has a large impact on the market. Learn how to interpret the most important reports. Economic Indicators To Know
There are human tendencies that can block the road toward achieving our financial goals. Here's how to get around them. 3 Psychological Quirks That Are Killing Your Trading
This tool smooths trends and makes them easier to indentify. Confirm Forex Momentum With Heikin Ashi
Find out how to use these technical analysis building blocks. Exploring Oscillators and Indicators
It's possible to pick a top or bottom with no indicator support. We'll show you how this strategy works. Seven-Day Extension Fade
Can butter production help you predict the market's next move? Find out here. World's Wackiest Stock Indicators
This reversal pattern can make sense of the seeming randomness of market movements and improve your trading. A Trader's Guide To Using Fractals
How do I use the Nova/Ursa ratio?
The tenets of market psychology underlie each and every charting tool. Trading Psychology And Technical Indicators
This widely watched indicator of economic well-being also directly influences the market. What You Need To Know About The Employment Report
Use this indicator to validate a change in price direction and moving averages. Volume Oscillator Confirms Price Movements

(DOD, NATO) In intelligence usage, an item of information which reflects the intention or capability of a potential enemy to adopt or reject a course of action.

1. any substance used in a chemical operation to indicate by a colour change the completion of a reaction or the attainment of a desired state.
2. any substance that by a characteristic colour change indicates the presence of another particular substance.
3. (in saturation analysis) the labelled substance whose distribution between the reactants of the system is used to determine the amount of analyte present.
4. an isotope, often a radioactive one, that is used as a tracer.

Previous:	indicated hydrogen, indican, index
Next:	indicator enzyme, indicator organism, indicator yellow

1. a piece of information that suggests a suitable line of action, in diagnosis, treatment or control.
2. any substance that indicates the appearance or disappearance of a chemical by a color change or attainment of a certain pH.

• i. plants — plants (e.g. Astragalus and Xylorrhiza spp.) that prefer a higher than normal soil content of a particular element, e.g. selenium, copper. Their presence indicates a potentially poisonous pasture. Called also obligate accumulator plants.

n

A mark or symptom specific to a condition or disease.

For a list of words related to indicator, see:

• Substances, Particles, and Atomic Architecture - indicator: substance used to show the presence of a substance or ion by its color
• Tools, Tests, Units, and Scales - indicator: any substance, such as litmus paper, used to show the presence of a substance or ion by its color
• Parts, Practices, and Argot - indicator: illuminated designation of train’s number on locomotive and caboose

---

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
n. - indikator, viser, måleapparat, måler

Nederlands (Dutch)
aanwijzing, indicator, meetgegeven, mededelingenbord, knipperlicht

Français (French)
n. - indicateur, indication, indice, clignotant, (Rail) tableau, (Ling, Chim) indicateur

Deutsch (German)
n. - Anzeiger, Indikator, Fahrtrichtungsanzeiger, Zeiger

Ελληνική (Greek)
n. - δείκτης, πίνακας

Italiano (Italian)
indice, lampeggiatore

Português (Portuguese)
n. - indicador (m)

Русский (Russian)
указатель

Español (Spanish)
n. - indicador, señal, luz intermitente

Svenska (Swedish)
n. - visare, indikator (tekn. o kem.), mätare, tecken (bildl.), anslagstavla, skylt, blinker

中文（简体）(Chinese (Simplified))
指示器, 指示剂

中文（繁體）(Chinese (Traditional))
n. - 指示器, 指示劑

한국어 (Korean)
n. - 지시자, 척도, 반응 지시약, 경제 지표

日本語 (Japanese)
n. - 指し示すもの, 徴候, 表示器, 指示する人, 指針

العربيه (Arabic)
‏(الاسم) مؤشر, دليل‏

עברית (Hebrew)
n. - ‮מצביע, מחוון, מחוג, אור איתות, אינדיקטור, סימן‬

If you are unable to view some languages clearly, click here.

Some good "indicator" pages on the web: