Skip to Content
Medical Term:


Pronunciation: som-nam'byu-lizm


  1. A disorder of sleep involving complex motor acts that occurs primarily during the first third of the night but not during REM sleep.
  2. A form of hysteria in which purposeful behavior is forgotten.

Synonym(s): oneirodynia activa, sleepwalking, somnambulance

[L. somnus, sleep, + ambulo, to walk]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.