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definitions

phreno-

  1. a combining form meaning “mind,” “diaphragm,” used in the formation of compound words: phrenology.
Also especially before a vowel, phren-.

Origin of phreno-

< Greek phreno-, combining form representing phrḗn mind, diaphragm
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for phreno-

phreno-

before a vowel phren-

combining form
  1. mind or brainphrenology
  2. of or relating to the diaphragmphrenic

Word Origin for phreno-

from Greek phrēn mind, diaphragm
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 phreno-

before vowels phren-, word-forming element meaning "mind," also "diaphragm," from Greek phreno-, comb. form of phrene properly "diaphragm, muscle which parts the abdomen from the thorax;" in Homer extended to "parts around the heart, breast," hence "heart" (as a seat of passions), "mind, seat of thoughts, wits, senses," of unknown origin.

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

phreno-

pref.
  1. Mind:phrenoplegia.
  2. Diaphragm:phrenogastric.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.