familial dysautonomia
nounMedical Definition of familial dysautonomia
: a disorder of the autonomic nervous system that is inherited as an autosomal recessive trait, typically affects individuals of eastern European Jewish ancestry, and is characterized especially by excessive sweating and salivation, lack of tears, difficulty in swallowing, corneal ulceration, orthostatic hypotension, poor thermoregulation, episodic vomiting, sensory deficits (as of taste and pain), and emotional instability
— called also Riley-Day syndrome