Definition of R
1. Noun. A unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air.
Generic synonyms: Radioactivity Unit
2. Noun. (physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole.
Category relationships: Natural Philosophy, Physics
Generic synonyms: Constant
3. Noun. The 18th letter of the Roman alphabet.
Generic synonyms: Alphabetic Character, Letter, Letter Of The Alphabet
4. Noun. The length of a line segment between the center and circumference of a circle or sphere.
Group relationships: Diam, Diameter
Specialized synonyms: Semidiameter, Radius Of Curvature
Generic synonyms: Length
Definition of R
1. Letter. (Latn-def en letter 18 ar) ¹
2. Number. (Latn-def en ordinal 18 ar) ¹
3. Abbreviation. (context: US politics) Republican ¹
4. Abbreviation. (''film certification'') restricted ¹
5. Abbreviation. reverse ¹
6. Abbreviation. right (''as opposed to left'') ¹
7. Abbreviation. (context: handbells) ring ¹
8. Abbreviation. (chess) rook ¹
9. Abbreviation. (context: baseball cricket) The statistic reporting the number of runs scored by a player ¹
10. Abbreviation. Thursday ¹
11. Letter. (Latn-def en letter 18 ar) ¹
12. Number. (Latn-def en ordinal 18 ar) ¹
13. Verb. (context: abbreviation slang text messaging internet) are (qualifier in text messaging and internet conversations) ¹
¹ Source: wiktionary.com
Medical Definition of R
1. Commonly used abbreviation for respiration(s). For example, in a medical chart, you might see scrawled bp90/60 t98.6 hr 60/reg r15 , which is short hand signifying that the blood pressure is 90/60 mm hg, the temperature (t) is 98.6 degrees fahrenheit, the heart rate (hr) is 60/min and regular, and the respirations (r) 15/min. (this example would be entirely normal for an adult or older child). Symbol for a ring chromosome, a structurally abnormal chromosome in which the end of each chromosome arm has been lost and the broken arms have been reunited in ring formation. (12 Dec 1998)
Lexicographical Neighbors of R