- Holland’s theory of vocational choice
- Hollenberg figure
- Hollerith
- Holley
- Holley inequality
- Holliday junction
- Hollis Burnle Chenery
- Hollmann circuit
- Holloko
- hollow
- Holloway formula
- hollow beam
- hollow blow molding
- hollow blow molding machine
- hollow blow moulding
- hollow catchoed light source
- hollow cathode lamp
- hollow-cathode lamp
- hollow cathode lamp (HCL)
- hollow circular cylinder
- hollow-core bragg fiber
- hollow core optical fiber
- hollow core optical fiber laser
- hollow cup motor
- hollow discharge