R (EN)

letter, noun, adjective, symbol

letter “R”

1. the uppercase form of the letter "r"
   Sign up to see the translation of definitions and examples into any language.

   Rachel wrote her name with a capital R at the beginning.

noun “R”

1. an abbreviation of Republican (in the US)
   It will be Donald Trump (R) vs. Joe Biden (D).
2. in legal contexts, it represents the crown or government in court cases (from Latin "rex" = king)
   In the case of R v Johnson, the prosecution was brought by the state.
3. abbreviation of Thursday in academic schedules
   My classes are scheduled for M T W R, with Thursdays being my longest day.

adjective “R”

1. movie rating "restricted" (not suitable for children under a certain age without adult supervision)
   The movie was rated R, so anyone under 17 needed an adult to accompany them.
2. an abbreviation of "reverse" (used e.g. in cars)
   Put the car in R for backing up.
3. right (direction)
   Press the R key on the controller.

symbol “R”

1. Rand (South African currency)
   I exchanged my dollars for R500 to spend during my trip to South Africa.
2. symbol for a rook in chess
   R to H8 puts the opponent's king in check.
3. roentgen (the unit of measurement for the amount of ionizing radiation)
   The X-ray machine was calibrated to emit a dose of 5 R to ensure it was safe for diagnostic use.
4. symbol for electrical resistance (in physics)
   You can use the formula R = V/I, where V is voltage, and I is current.
5. an unspecified radical in organic chemistry
   In the molecule RCOOH, "R" represents any alkyl group attached to the carboxylic acid group.
6. in genetics, a 1-letter abbreviation for any purine
   In the DNA sequence, an "R" indicates the presence of either adenine or guanine at that position.
7. the symbol for the amino acid arginine in biochemistry
   In the protein sequence, "R" stands for arginine, an amino acid important for muscle metabolism.