Myo- (prefix): A prefix denoting a relationship to muscle.
Myo- enters into many words and terms in medicine including cardiomyopathy, dermatomyositis, electromyography, leiomyoma, myocardial infarction, myocarditis, myocardium, myoclonic, myocyte, myopathy, myoglobin, myometrium, myotonia, myotonic dystrophy, and polymyositis.