English abbreviations from rr to rrd
- RR (Recoilless rifle)
- RR. (Rerum ("Of Things, Subjects" e.g. SS. RR. Ital., Writers on Italian [historical] subjects); Regesta)
- RR&D (Reparation, Removal, and Demolition Section, U. S. Military Government, Germany)
- RRA (Rapid Rural Appraisal)
- Rrad (Radiation Resistance)
- RRAP (Residential Rehabilitation Assistance Program)
- RRAS (Routing and Remote Access Service)
- RRAT ((celestial object) Rotating Radio Transient, a population of rotating neutron stars that produce periodic bursts of emission that are separated by intervals of minutes or hours)
- RRB (Railroad Retirement Board)
- RRBC (Release-to- Release Binary Compatibility)
- RRBI (Radar Range Bearing Indicator)
- RRC (Relatives Raising Children)
- RRCA (Road Runner Clubs of America)
- RRCB (Royal Racing Club de Bruxelles)
- RRCC (Regional Response Coordination Center)
- RRD (Receive, Record, Display)