| Acronym | Definition |
|---|
| HO | High Output |
| HO | Hands-On |
| HO | Head Office |
| HO | Honduras (Swan Islands) |
| HO | Hand-Over |
| HO | Home Office |
| HO | Holstein (cattle breed) |
| HO | Homeowners (multiple line insurance policy covering both property and liability for homeowners) |
| HO | High Order |
| HO | Hold On |
| HO | Handout |
| HO | Hold Off |
| HO | Honest Opinion |
| HO | Hoger Onderwijs (Dutch) |
| HO | Hand Off |
| HO | Holmium |
| HO | Hammer On (guitar technique) |
| HO | Hide Out |
| HO | Hearing Officer |
| HO | Heavy Oil |
| HO | Hippocratic Oath |
| HO | Hydrographic Office |
| HO | House Officer |
| HO | Hydrogen/Oxygen |
| HO | History Office |
| HO | Harmonic Oscillator |
| HO | Headquarters Office |
| HO | Heterotopic Ossification (orthopedics) |
| HO | Hostilities Only |
| HO | Hearing Office (Social Security) |
| HO | Hinder Ordonnantie (Indonesian: Hinder Ordinance) |
| HO | Handelsorganisation (GDR trade organization) |
| HO | Humanitarian Operation |
| HO | Heavy Offense (gaming) |
| HO | Hand Orthosis |
| HO | Hurst Olds (automobile) |
| HO | Hospitalisation d'Office (French) |
| HO | Hardware Overhead |
| HO | Hip Orthosis |
| HO | Hip Opener (stretching exercise) |
| HO | Hierorts (Austrian German: local or locally) |
| HO | Half O Scale |
| HO | Height Obstacle |
| HO | Horizontal Overscan |