R & R Definition
abbreviation
Rest and recuperation (leave)
Webster's New World
Rest and relaxation (or recreation)
Webster's New World
Rock-and-roll.
Webster's New World
(US politics) Republican.
Wiktionary
(film certification) Restricted.
Wiktionary
letter
numeral
The ordinal number eighteenth, derived from this letter of the English alphabet, called ar and written in the Latin script.
Wiktionary
noun
(law) Abbreviation of railroad.
Wiktionary