What does r mean?

Definitions for r

This dictionary definitions page includes all the possible meanings, example usage and translations of the word r.

Princeton's WordNet

  1. roentgen, Rnoun

    a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air

  2. gas constant, universal gas constant, Rnoun

    (physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole

  3. R, rnoun

    the 18th letter of the Roman alphabet

  4. radius, rnoun

    the length of a line segment between the center and circumference of a circle or sphere

Samuel Johnson's Dictionary

  1. R

    Is called the canine letter, because it is uttered with some resemblance to the growl or snarl of a cur: it has one constant sound in English, such as it has in other languages; as red, rose, more, muriatick: in words derived from the Greek, it is followed by an h, rhapsody: r is never mute, unless the second r may be accounted mute, where two rr are used; as myrrh.


  1. R

    R, or r, is the 18th letter of the modern English alphabet and the ISO basic Latin alphabet. Its name in English is ar (pronounced ), plural ars, or in Ireland or .


  1. r

    The term "r" can have various meanings depending on the context. Here are a few possible definitions: 1. Mathematics/Statistics: r usually represents a variable or a constant. It is popularly used to represent the radius in geometry, correlation coefficient in statistics, or a real number in algebra. 2. Physics/Chemistry: it is often used to denote the distance between two points or a position vector. 3. Programming: R is a programming language used for statistical computing and graphics. 4. Biology: the growth rate or reproduction rate in epidemiology. 5. Music: In musical annotation, r stands for rest or a silent beat. 6. Other: In other contexts, "R" can represent other things, such as a rating for Restricted movies, a symbol for gas constant, etc. These definitions should be understood in the context in which they are used.

Webster Dictionary

  1. R

    r, the eighteenth letter of the English alphabet, is a vocal consonant. It is sometimes called a semivowel, and a liquid. See Guide to Pronunciation, // 178, 179, and 250-254


  1. R

    R is the eighteenth letter of the ISO basic Latin alphabet.

The Standard Electrical Dictionary

  1. R

    (a) Abbreviation and symbol for Reamur, as 10º R., meaning 10º by the Reamur thermometer. (See Reamur Scale.) (b) Symbol for resistance, as in the expression of Ohm's Law C=E. (rho, Greek r) Symbol for specific resistance.

Dictionary of Nautical Terms

  1. r

    In the muster-book means run, and is placed against those who have deserted, or missed three musters.

Suggested Resources

  1. r

    The r symbol -- In this Symbols.com article you will learn about the meaning of the r symbol and its characteristic.

  2. r

    Quotes by r -- Explore a large variety of famous quotes made by r on the Quotes.net website.

  3. r

    Song lyrics by r -- Explore a large variety of song lyrics performed by r on the Lyrics.com website.

How to pronounce r?

How to say r in sign language?


  1. Chaldean Numerology

    The numerical value of r in Chaldean Numerology is: 2

  2. Pythagorean Numerology

    The numerical value of r in Pythagorean Numerology is: 9

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Translations for r

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