- Anteflexion - see Anteversion
- Antenatal
- Antepartum - see condition
- Anterior - see also condition
- Antero-occlusion 524.24
- Anteversion
- Anthracosilicosis (occupational) 500
- Anthracosis (lung) (occupational) 500
- Anthrax 022.9
- Anthropoid pelvis 755.69
- Anthropophobia 300.29
- Antibioma, breast 611.0
- Antibodies
- Antibody deficiency syndrome
- Anticoagulant, intrinsic, circulating, causing hemorrhagic disorder (see also Circulating anticoagulants) 286.5
- Antimongolism syndrome 758.39
- Antimonial cholera 985.4
- Antisocial personality 301.7
- Antithrombinemia (see also Circulating anticoagulants) 286.5
- Antithromboplastinemia (see also Circulating anticoagulants) 286.5
- Antithromboplastinogenemia (see also Circulating anticoagulants) 286.5
- Antitoxin complication or reaction - see Complications, vaccination
