R&B Acceptable in references for rhythm and blues if clear in the context: Randy Brecker is a jazz, rock, and R&B performer.

racquet Not racket, for the light bat used in tennis and badminton (exception to AP style).

RAM Acceptable in all references to random access memory (computer terminology).

rebut, refute Rebut means to argue to the contrary: He will rebut the allegation. Refute connotes success in argument, in proving something to be false or mistaken: Now that the charges have been refuted, he is taking a long vacation.

referendum (singular), referenda (plural): This preferred plural is an exception to AP style, which uses referendums.

résumé Use the accented é.

revolution Capitalize when part of the name of a specific historic event: the American Revolution, the French Revolution. Lowercase in all other uses: a revolution, the American and French revolutions.

river Capitalize as part of a proper name: the Mississippi River. Lowercase in all other uses: the river, the Mississippi and Missouri rivers. The Rio Grande stands alone as a name: rio means river in Spanish.

rock ’n’ roll But Rock and Roll Hall of Fame (a proper name).

Rosh Hashanah The Jewish new year; occurs in September or October. (This is the Chicago Manual and the first Merriam-Webster spelling; AP style uses the variant Rosh Hashana.)

ROM Acceptable in all references to read-only memory (computer terminology).

ROTC Acceptable in all references for Reserve Officers’ Training Corps.

RSS Acceptable in all references for Really Simply Syndication. Also: RSS feed.

RSVP This abbreviation for the French repondez s’il vous plait means “please reply.” Don’t use the redundant please RSVP.