altitude sickness 
noun [mass noun]
Illness caused by ascent to high altitude, characterized by hyperventilation, nausea, and exhaustion resulting from shortage of oxygen.He finally had to feign illness due to altitude sickness and return to Beijing to be re-assigned to another post....
- They will be at risk of many other illnesses besides altitude sickness.
- Indeed Spanish Jesuit fathers in South America were the first in Western literature to document the symptoms of altitude sickness.
- PABA
- pabble
- pablum
- Pabst
- pabular
- pabulum
- PABX
- PAC
- paca
- pacai
- well-imagined
- well-imitated
- well, I'm (or I'll be) buggered
- well-improved
- well in
- well-inclined
- well I never! (or well I never did!)
- well informed
- wellington
- Wellington, 1st Duke of
- Wellington apple
- wellington boot
- wellingtonia
- Wellingtonian
- well-inhabited