Encyclopedias, Almanacs, Transcripts, and Maps
- Resistance (Inertia)
- Resource Conservation and Recovery Act
- Resource Recovery
- Resources for the Future
- Respiratory Diseases
- Restoration drama
- retail price index
- Retention Time
- Revel, Bernard
- Revenge and Retribution
- reversible reaction
- Revival and Renewal
- Revolutions of 1989
- Rheas (Rheidae)
- rhesus
- Rhinoceroses
- Rhinoceroses (Rhinocerotidae)
- rhodophyte
- Rhombozoa (Rhombozoans)
- rhythm and blues