XYY syndrome
[ ĕks′wī-wī′ ]
n.
A chromosomal anomaly characterized by the presence of one X-chromosome and two Y-chromosomes and thought to be associated with tallness, aggressiveness, and acne.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.