- Adrenal gland - see condition
- Adrenalism 255.9
- Adrenalitis, adrenitis 255.8
- Adrenarche, precocious 259.1
- Adrenocortical syndrome 255.2
- Adrenogenital syndrome (acquired) (congenital) 255.2
- Adrenoleukodystrophy 277.86
- Adrenomyeloneuropathy 277.86
- Adventitious bursa - see Bursitis
- Adynamia (episodica) (hereditary) (periodic) 359.3
- Adynamic
- Aeration lung, imperfect, newborn 770.5
- Aero-otitis media 993.0
- Aerobullosis 993.3
- Aerocele - see Embolism, air
- Aerodermectasia
- Aerodontalgia 993.2
- Aeroembolism 993.3
- Aerogenes capsulatus infection (see also Gangrene, gas) 040.0
- Aerophagy, aerophagia 306.4
- Aerosinusitis 993.1
- Aerotitis 993.0