Ancient Greek word root · Number & Measure

metr-: measure

metr- is an Ancient Greek root meaning “measure”. Learn its variants and explore 19 connected words.

Meaning and variants

Meaning: measure

Root forms: metr-, -meter, -metry

Source word: μέτρον — something used to measure: measure, rule, weight

Word family and examples

• diameter

  a straight line passing through the center of a circle

• geometry

  the branch of mathematics concerned with points, lines, surfaces, and solids

• perimeter

  The sum of the distance of all the lengths of the sides of an object.

• symmetry

  Exact correspondence on either side of a dividing line, plane, center or axis.

• thermometer

  an instrument for measuring temperature

• barometer

  An instrument for measuring atmospheric pressure.

• telemetry

  the automatic measurement and transmission of data from remote sources

• trigonometry

  The branch of mathematics that deals with the relationships between the sides and angles of (in particular) right-angled triangles, as represented by the trigonometric functions, and with calculations based on said relationships.

• optometry

  The art and science of vision and eye care.

• speedometer

  An instrument located within the dashboard of a vehicle that measures and indicates the current speed of the vehicle.

• altimeter

  An apparatus for measuring altitude.

• odometer

  An instrument, usually embedded within the speedometer of a vehicle, that measures the distance the vehicle has traveled since production.

• micrometer

  A device used to measure distance very precisely but within a limited range, especially depth, thickness, and diameter.

• chronometer

  A device for measuring time, particularly a precision mechanism for measuring time of day.

• pedometer

  A device, often electronic, that measures the number of steps taken, and thus estimates the distance walked.

• photometry

  The measurement of various aspects of light, especially its intensity.

• stoichiometry

  The study and calculation of quantitative (measurable) relationships of the reactants and products in chemical reactions (chemical equations).

• calorimetry

  The science of measuring the heat absorbed or evolved during the course of a chemical reaction or change of state.

• calorimeter

  An apparatus for measuring the heat generated or absorbed by either a chemical reaction, change of phase or some other physical change.

Root connections help with vocabulary recall. They are not a complete etymological history, and a spelling match alone does not prove a relationship.

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