sort by Rank | Alpha
| Possible Meanings | Rank |
| An Adoption Taxpayer Identification Number | *** |
| acute tubulo-interstitial nephropathy | ** |
| Adoption Taxpayer Identification Numbers | ** |
| Arizona Tobacco Information Network | ** |
| Adoption Taxpayer ID Number | * |
| Alternatives to Incarceration Network | * |
| Alien TIN (replaced by ITIN) | * |