decompensation

de- +‎ compensation

• (UK) IPA^(key): /diːˌkɒmpɛnˈseɪʃən/

decompensation (countable and uncountable, plural decompensations)

1. (medicine) The inability of a diseased or weakened organic system or organ to compensate for its deficiency, resulting in functional deterioration.
   • 1982, Pamela Martyn, “If You Guessed Cardiovascular Disease, Guess again”, in American Journal of Nursing, volume 82, number 8, page 1239:

     Once it was determined that hyperthyroidism was the probable etiology of her cardiac decompensation, the next step was treatment of the underlying disease.

2. (psychology) The deterioration of cognitive or emotional functionality in a person who is distressed or who suffers from a psychological disorder.
   • 1945 May, William C. Menninger, “The Mentally or Emotionally Handicapped Veteran”, in Annals of the American Academy of Political and Social Science, volume 239, page 21:

     A varying percentage of our combat soldiers reach the limit of their endurance and must leave their foxholes, not for physical wounds but because of emotional decompensation.

• decompensate

• Oxford English Dictionary, 2nd ed., 1989.
• Random House Webster's Unabridged Electronic Dictionary, 1987-1996.