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definitions

hypno-

  1. a combining form meaning “sleep,” “hypnosis,” used in the formation of compound words: hypnotherapy.
Also especially before a vowel, hypn-.

Origin of hypno-

< Greek hýpno(s) sleep; see Hypnos
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for hypno-

hypno-

before a vowel hypn-

combining form
  1. indicating sleephypnophobia
  2. relating to hypnosishypnotherapy

Word Origin for hypno-

from Greek hupnos sleep
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
Word Origin and History for hypno-

word-forming element meaning "sleep," from Greek hypno-, comb. form of hypnos "sleep" (see somnolence).

Online Etymology Dictionary, © 2010 Douglas Harper
hypno- in Medicine

hypno-

pref.
  1. Sleep:hypnolepsy.
  2. Hypnosis:hypnoanalysis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.