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definitions

fragile X syndrome

noun
  1. a widespread form of mental retardation caused by a faulty gene on the X chromosome.

Origin of fragile X syndrome

First recorded in 1980–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
fragile x syndrome in Medicine

fragile X syndrome

n.
  1. An inherited disorder causing mental retardation, enlarged testes, and facial abnormalities in males and mild mental retardation in females.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.