- Random Copolymer
- Recovery (Strain)
- Recrystallization
- Recrystallization Temperature
- Rectifying Junction
- Reduction
- Reflection of Light
- Refraction of Light
- Refractory
- Reinforced Concrete
- Relative Permeability
- Relaxation Modulus
- Remanence
- Residual Stress
- Resilience
- Resistivity
- Resolved Shear Stress
- Reverse Biase
- Rolling