There are multiple definitions:

1. Assistive Technology Act of 1998(English)

   • replaces TRAID
   • TRAID
   • Medical technology (assessment)

2. American Thyroid Association(English)

   • Thyroid and parathyroid, Organizations (clinical)
   • http://www.thyr…id-association/

3. atmosphere absolute(English)

   • sea level pressure
   • HBO, UHMS
   • Oxygen, Physiology
   • https://www.uhms.org/

4. aspirin-tolerant asthma(English)

   • AIA, AP, LT, LTC4S, NSAID
   • Asthma
   • https://doi.org…mai.2000.107603

5. atrial tachyarrhythmia(English)

   • AF, PVI
   • Cardiology, Electrophysiology
   • https://doi.org…0392-015-0890-8

6. attosecond transient absorption(English)

   • ATDM, ETDM
   • Spectroscopy
   • https://doi.org…srt.2016.01.004