a combining form meaning “muscle,” used in the formation of compound words: myology.
Also especially before a vowel, my-.
Origin of myo-
combining form representing Greek mŷs mouse, muscle
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
before a vowel my-
Word Origin for myo-
from Greek mus muscle
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
before vowels my-, word-forming element meaning "muscle," from comb. form of Greek mys "muscle," literally "mouse" (see muscle (n.)).
Online Etymology Dictionary, © 2010 Douglas Harper
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.