| Acronym | Definition |
|---|
| III | 3 (Roman numeral) |
| III | Insurance Information Institute |
| III | Regiment (Graphical Representation/Military) |
| III | International Industries, Inc. (Washington, DC) |
| III | Industry Institute Interaction (India) |
| III | Innovative Interfaces Inc. |
| III | International Information Infrastructure |
| III | Institute for Information Industry |
| III | Ispat Inland, Inc. (Indiana) |
| III | Interfaculty Initiative in Information Studies (Japan) |
| III | Intel Interchangeability Initiative |
| III | International Information Issues |
| III | Instituto Indigenista Interamericano (Inter-American Indian Institute) |
| III | Interstate Identification Index |
| III | Institute of Infection and Immunity (Canada) |
| III | Triremis (Latin: Triremes, epigraphy) |
| III | Insurance Institute of India |
| III | Integrated Information Infrastructure |
| III | Interactive Investor International |
| III | Incapacitating Illness or Injury |
| III | Informis Infinitas Inhumanitas (band) |
| III | Immediate Intensive Intervention |
| III | Integrated Imagery and Intelligence |
| III | Intelligence Integrity Intensity |
| III | Indian Institute of Immunology |