| An | atmosphere normal |
|---|---|
| AT | abdominal thrusts; achievement test; Achilles tendon; Achard-Thiers [syndrome]; adaptive thermogenes... |
| ATA | alimentary toxic aleukia; American Thyroid Association; aminotriazole; antithymic activity; antithyr... |
| ATM | abnormal tubular myelin; acute transverse myelopathy; asynchronous transfer mode; atmosphere |
| atm | standard atmosphere |