| IAST | I Am So Tired 
| Others |
| IAST | Ideal Adsorbed Solution Theory
| Others |
| IAST | Independent Assurance Sampling and Testing
| Others |
| IAST | India Association of Southeast Texas
| Others |
| IAST | Industry Access Service Tariff
| Others |
| IAST | Inhalation Allergy Screen Test
| Others |
| IAST | Institute for Advanced Science and Technology
| Others |
| IAST | Institute for Advanced Study in Toulouse
| Others |
| IAST | Institute of Applied Science and Technology
| Others |
| IAST | Interactive Application Security Testing
| Others |
| IAST | Internation Alphabet of Sanskrit Transliteration
| Others |
| IAST | International Academy for the Study of Tourism
| Others |
| IAST | International Activities Staff
| Others |
| IAST | International Alphabet of Sanskrit Transliteration
| Others |