RCM
- Interference reflection microscopy
- Kindertransport
- Montreal Citizens' Movement
- Nintendo Switch system software
- Piledriver (microarchitecture)
- RADARSAT Constellation
- Rapid Communications in Mass Spectrometry
- Reciprocating Chemical Muscle
- Regimental Corporal Major
- Regional county municipality
- Regulatory Compliance Mark
- Reliability-centered maintenance
- Restrictive cardiomyopathy
- Revenue cycle management
- Reverse Cuthill–McKee algorithm
- Richmond Airport (Queensland)
- Ring-closing metathesis
- Rockefeller Capital Management
- Rokos Capital Management
- Rotor current meter
- Royal Canadian Mint
- Royal College of Midwives
- Royal College of Music
- Royal Cornwall Museum
- The Royal Conservatory of Music