1. Characterized by effort to the point of exhaustion; especially physical effort
   - arduous, grueling [US], gruelling [Brit, Cdn], hard, heavy, laborious, operose, punishing, toilsome

See also: effortful

• Myliobatidae
• Mylitta
• mylodon
• mylodontid
• Mylodontidae
• mylonite
• mym
• myna
• myna bird
• mynah
• mynah bird
• MYOB
• myocardial
• myocardial infarct
• myocardial infarction
• myocardial inflammation
• myocardiopathy
• myocarditis
• myocardium
• Myocastor
• Myocastor coypus
• myoclonus
• myoclonus epilepsy
• myodynia
• myofascial pain syndrome