noun Pathology.
a tendency to sleep excessively.

1875–80; hyper- + (in)somnia

hypersomniac, noun
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To hypersomnia
American Heritage
Medical Dictionary

hypersomnia hy·per·som·ni·a (hī'pər-sŏm'nē-ə)
A condition in which one sleeps for an excessively long time but is normal in the waking intervals.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature