A thermometer is a tool that measures temperature — how hot or cold something is. Thermometers are used to see if you have a fever or tell you how cold it is outside.

Made up of thermo (heat) and meter (measuring device), the meaning of the word thermometer is pretty straightforward. Thermometers measure temperatures in degrees, according to either the Celsius or Fahrenheit system. Meteorologists use thermometers to find out how hot it is or if it's below freezing. Doctors use thermometers to check your body temperature — a very high or low body temperature means you're sick.

Definitions of thermometer
  1. noun
    measuring instrument for measuring temperature
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    alcohol thermometer, alcohol-in-glass thermometer
    thermometer consisting of a glass capillary tube marked with degrees Celsius or Fahrenheit and containing alcohol which rises or falls as it expands or contracts with changes in temperature
    candy thermometer
    a thermometer used to determine the temperature of candy syrups during cooking
    Centigrade thermometer
    a thermometer calibrated in degrees centigrade
    a thermometer designed to measure low temperatures
    dry-bulb thermometer
    an ordinary thermometer with a dry bulb; used to measure the air temperature
    Fahrenheit thermometer
    a thermometer calibrated in degrees Fahrenheit
    air thermometer, gas thermometer
    thermometer that measures temperature by changes in the pressure of a gas kept at constant volume
    maximum and minimum thermometer
    thermometer that records the highest and lowest temperatures reached during a period of time
    meat thermometer
    a thermometer that is inserted into the center of a roast (with the top away from the heat source); used to measure how well done the meat is
    mercury thermometer, mercury-in-glass thermometer
    thermometer consisting of mercury contained in a bulb at the bottom of a graduated sealed glass capillary tube marked in degrees Celsius or Fahrenheit; mercury expands with a rise in temperature causing a thin thread of mercury to rise in the tube
    oven thermometer
    a thermometer that registers the temperature inside an oven
    a thermometer designed to measure high temperatures
    Reaumur thermometer
    an alcohol thermometer calibrated in degrees Reaumur
    platinum thermometer, resistance thermometer
    thermometer that measures temperature by changes in the resistance of a spiral of platinum wire
    reversing thermometer
    a thermometer that registers the temperature in deep waters
    self-registering thermometer
    a thermometer that records the temperature automatically
    a thermometer that registers the temperature at some distant point
    thermocouple, thermocouple junction
    a kind of thermometer consisting of two wires of different metals that are joined at both ends; one junction is at the temperature to be measured and the other is held at a fixed lower temperature; the current generated in the circuit is proportional to the temperature difference
    electric thermometer, thermel, thermoelectric thermometer
    a thermometer that uses thermoelectric current to measure temperature
    thermograph, thermometrograph
    a thermometer that records temperature variations on a graph as a function of time
    a kind of thermometer for measuring heat radiation; consists of several thermocouple junctions in series
    wet-bulb thermometer
    a thermometer with a bulb that is covered with moist muslin; used in a psychrometer to measure humidity
    Beckman thermometer
    a mercury thermometer that measures small differences or changes in temperature
    clinical thermometer, mercury-in-glass clinical thermometer
    a mercury thermometer designed to measure the temperature of the human body; graduated to cover a range a few degrees on either side of the normal body temperature
    optical pyrometer, pyroscope
    a pyrometer that uses the color of the light emitted by a hot object
    pyrometric cone
    a pyrometer consisting of a series of cones that melt at different temperatures
    radiation pyrometer
    a pyrometer for estimating the temperature of distant sources of heat; radiation is focussed on a thermojunction connected in circuit with a galvanometer
    resistance pyrometer
    pyrometer that measures high temperatures by the resistance in a heated wire
    type of:
    measuring device, measuring instrument, measuring system
    instrument that shows the extent or amount or quantity or degree of something
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