| Hourly Precipitation Data | Academic & Science |
| Half Power Diameter | Academic & Science |
| Holistic Probabilistic Design | Academic & Science |
| Hermitian Positive Definite | Academic & Science |
| Histrionic Personality Disorder | Academic & Science |
| Hrvatsko Psihološko Društvo | Academic & Science |
| Croatian Psychological Society | Academic & Science |
| Household Products Database | Business |
| High Performance Designs | Business |
| Hypnotherapy Practitioners Diploma | Business |
| Hockey Player Development | Community |
| Honda Performance Development | Community |
| Housing Preservation and Development | Community |
| Human Potential Development | Community |
| housing preservation | Community |
| Housing Preservation Development | Community |
| Housing Preservation And | Community |
| Hydrographic Production Database | Computing |
| High Point Driver | Computing |
| High Performance Design | Computing |
| Hot Plug Detect | Computing |
| Human Pathway Database | Computing |
| Hpdex | Cryptocurrency |
| Hits Per Day | General |
| High Power Discriminator | General |
| Human Presence Detection | General |
| High Performance Delivery | General |
| Hybrid Performance Development | General |
| High Performance Diesel | General |
| High Performance Driving | General |
| High Performance Days | General |
| High Performance Derivative | General |
| High Performance Damper | General |
| Highway Patrol Division | General |
| Hyundai Performance Development | General |
| Head Protection Device | General |
| Historic Preservation Division | General |
| High Performance Dish | General |
| Hana Project Dubs | General |
| HotDocs PDF Document | General |
| High Precision Devices | General |
| High Posterior Density | General |
| Honor Pride and Dedication | General |
| Houston Paradox of Double | General |
| Histrionic Pedophilia Disorder | General |
| Hailey Police Department | Governmental |
| Humphrey Police Department | Governmental |
| Hearing Protection Device | Governmental |
| Harrisonburg Police Department | Governmental |
| Honolulu Police Department | Governmental |
| Houston Police Department | Governmental |
| Hingham Police Department | Governmental |
| Houston Police | Governmental |
| Houston Police Department's | Governmental |
| Houston Police Digital | Governmental |
| Healthcare Payments Data | Medical |
| Highest Posterior Density | Medical |
| Health Product Declaration | Medical |
| Healthcare Provider Directory | Medical |
| Health Product Declarations | Medical |