The Full Form of R&R is Rest & Recreation.

R&R, military slang for rest and recuperation (or rest and relaxation or rest and recreation or rest and rehabilitation), is an acronym used for the free time of a soldier or international UN staff serving in unaccompanied (no family) duty stations. The term is used by a number of militaries such as the United States Armed Forces and British Armed Forces. Jocular substitutes among soldiers include “A&A” (“ass and alcohol”), “I&I” (“intercourse and intoxication”), “P&P” (“pussy and popcorn”), including jocular interpretations of R&R such as “rape and restitution”, “rape and ruin”, “rape and run”. The US Morale, Welfare and Recreation network provides leisure services for US military personnel. In the UK, the term applies to a type of leave granted to personnel during an overseas deployment which allows them to return home to the UK to visit their family.