fragile-X syndrome
noun
an inherited condition characterized by mental subnormality: affected individuals have an X-chromosome that is easily damaged under certain conditions
RELATED CONTENT
What The “X” In “Xbox” Stands For?No letter in the English language gets around like X. The 24th letter of the alphabet shows up everywhere, from the popular Xbox to standing in for a signature on legal documents. It represents a chromosome, signifies the multiplication process, and marks “the spot” on treasure maps. Let’s explore just a few of the uses of this versatile letter. The story behind the X in Xbox …
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