| Abbreviation | Definition |
|---|---|
| HYT | High Year of Tenure |
| i.e. | Id Est (that is) |
| I2 | Internet 2 |
| IA | Import Administration |
| IA | Indian American |
| IA | Interim Assistance |
| IA | Internal Allocation |
| IAAC | Inter-Agency Advisory Committee |
| IACC | Infrastructure Assistance Coordinating Council |
| IAD | Information Access Division |
| IAD | International Affairs Department |
| IADB | Inter-American Development Bank |
| IADRWG | Interagency Alternative Dispute Resolution Working Group |
| IAEFOT | International Association for Ethical Organ transplant |
| IAEGC | Inter Agency Electronic Grants Committee |
| IAF | Inter American Foundation |
| IAF | Inter-American Foundation |
| IAFIE | International Association For Intelligence Education |
| IAQ | Indoor Air Quality |
| IARPA | Intelligence Advanced Research Projects Activity |