- Gyrification
- Gyro
- Gyrocompass
- Gyroid
- Gyroradius
- Gyroscopes
- Gyrotrons
- Gzip
- H channel
- H-bridge
- H-derivative
- H-infinity
- H-point
- H-reflex
- H1 receptor
- H1N1
- H2
- H2 receptor
- H2 receptor antagonists
- H2-receptor antagonists
- H37Rv
- H3K4me1
- H3N2
- H3k27me3
- H3k4me3
- H3k9me2
- H3k9me3
- H4k20me
- H7N7
- H9N2
- HACCP
- HAL
- HALE
- HALS
- HALT
- HAProxy
- HARA
- HATEOAS
- HAZ
- HAZOP
- HBB
- HBEGF
- HBM
- HBT
- HBV
- HBase
- HBsAg
- HCCI
- HCI
- HCNG