Select a letter to go to the terms beginning with that letter.
- HC
- Hydrocarbons
- HCCI
- Homogeneous Charge Compression Ignition
- HCFC
- Hydrochlorofluorocarbon
- HD
- Heavy-Duty (vehicle or lubricant)
- HDD
- Heavy-Duty Diesel
- HDDEO
- Heavy-Duty Diesel Engine Oil
- HDS
- Hydrogenated Styrene Diene
- HEUI
- Hydraulically Actuated Electronically Controlled Unit Injectors
- HEV
- Hybrid Electric Vehicles
- HFC
- Hydrofluorocarbon
- HFFI
- Heavy Fuel Flow Improver
- HFO
- Heavy Fuel Oil
- HFRR
- High Frequency Reciprocating Rig
- HGO
- Heating Gas Oil
- HP
- Horsepower
- HSD
- Hydrogenated Styrene Diene
- HSDI
- High Speed Direct Injection (diesel engine)
- HSE
- Health, Safety, Environment
- HSE (UK)
- Health and Safety Executive
- HTHS
- High Temperature High Shear