Definitions of indicator

  1. 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
  2. ( 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
  3. a device for showing the operating condition of some system
  4. a signal for attracting attention
  5. One who, or that which, shows or points out; as, a fare indicator in a street car.
  6. A pressure gauge; a water gauge, as for a steam boiler; an apparatus or instrument for showing the working of a machine or moving part
  7. An instrument which draws a diagram showing the varying pressure in the cylinder of an engine or pump at every point of the stroke. It consists of a small cylinder communicating with the engine cylinder and fitted with a piston which the varying pressure drives upward more or less against the resistance of a spring. A lever imparts motion to a pencil which traces the diagram on a card wrapped around a vertical drum which is turned back and forth by a string connected with the piston rod of the engine. See Indicator card ( below).
  8. A telltale connected with a hoisting machine, to show, at the surface, the position of the cage in the shaft of a mine, etc.
  9. The part of an instrument by which an effect is indicated, as an index or pointer.
  10. Any bird of the genus Indicator and allied genera. See Honey guide, under Honey.
  11. That which indicates the condition of acidity, alkalinity, or the deficiency, excess, or sufficiency of a standard reagent, by causing an appearance, disappearance, or change of color, as in titration or volumetric analysis.
  12. Any bird of the genus and allied genera. See Honey guide, under Honey.
  13. One who, or that which, points out; the part of an instrument by which an effect is pointed out.
  14. In chemical analysis a substance which renders visible the completion of a reaction; the color change in litmus, for example, denotes the formation of an acid or alkali or the neutralization of a solution.
  15. One who indicates: an instrument on a steam- engine to show the pressure.
  16. That which indicates, as a pointer.
  17. He who or that which points out or indicates; an apparatus which indicates steam pressure.
  18. He who or that which points out; a water- gauge in a steam- engine; in anat., the muscle which extends to the forefinger.

Usage examples for indicator

  1. Arcot fell into step with the planet as it moved about in its orbit, and watched the speed indicator carefully. – Invaders from the Infinite by John Wood Campbell
  2. Ishmael watched, checked the man at the turn, and finding the corn was flowing too freely, altered the indicator and then himself took the reins and in his turn went up and down the lines of smoking earth. – Secret Bread by F. Tennyson Jesse
  3. There is first the phonetic base, itself a character originally intended to represent some thing or idea, and then borrowed to represent other things and ideas similarly pronounced; and secondly, the indicator another character added to the phonetic base in order to distinguish between the various things and ideas for which the same phonetic base was used. – China and the Chinese by Herbert Allen Giles
  4. Move indicator to 273 on C scale. – Instruction for Using a Slide Rule by W. Stanley
  5. Mr. Callahan's first idea was to distribute gold quotations, and to this end he devised an " indicator – Edison, His Life and Inventions by Frank Lewis Dyer and Thomas Commerford Martin
  6. In the same month, Hunt published an affectionate farewell to him in The Indicator – Leigh Hunt's Relations with Byron, Shelley and Keats by Barnette Miller
  7. The " fraction" drum of the indicator could be driven in either direction, known as the advance and retrograde movements, and was divided and marked in eighths. – Edison, His Life and Inventions by Frank Lewis Dyer and Thomas Commerford Martin
  8. The indicator crept to ten feet, twenty, thirty. – Way of a Rebel by Walter M. Miller
  9. One indicator looked upon the Gold Room; the other opened toward the street. – Edison, His Life and Inventions by Frank Lewis Dyer and Thomas Commerford Martin
  10. " Thet," said Droop, slowly, " is an indicator of height above ground and tells yer direction." – The Panchronicon by Harold Steele Mackaye
  11. " Yes, until the indicator shows that the bag is full. – Tom Swift and his Air Glider or, Seeking the Platinum Treasure by Victor Appleton
  12. But the indicator's wrong? – Ralph of the Roundhouse by Allen Chapman
  13. A more correct test, however, may be made with the centre indicator – Modern Machine-Shop Practice, Volumes I and II by Joshua Rose
  14. He glanced up at the great disc of the indicator and frowned. – Flight From Tomorrow by Henry Beam Piper
  15. Joe shot a glance at his rate of climb indicator – Frigid Fracas by Dallas McCord Reynolds
  16. Tensely we watched the chart roll slowly down till the end of the channel passed the indicator – City of Endless Night by Milo Hastings
  17. Its reception- indicator was piously placed at " Ground." – The Pirates of Ersatz by Murray Leinster
  18. What's on our speed indicator – The Passing of Ku Sui by Anthony Gilmore
  19. The spring is made of such a strength, that when the cylinder of the indicator is perfectly exhausted, the pressure of the atmosphere may force its piston down within an inch of its bottom. – James Watt by Andrew Carnegie
  20. Thereupon John threw on the gas by degrees until the indicator showed them to be whizzing along at 150 miles. – Around the World in Ten Days by Chelsea Curtis Fraser