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definitions

functional disease

noun Pathology.
  1. a disease in which there is an abnormal change in the function of an organ, but no structural alteration in the tissues involved (opposed to organic disease).

Origin of functional disease

First recorded in 1870–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for functional disease

functional disease

noun
  1. a disease in which there is no observable change in the structure of an organ or partCompare organic disease
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012