HMM

HMM may refer to:

• Hammerton railway station, England, National Rail station code HMM.
• Heavy meromyosin, a fragment obtained from the muscle protein myosin II following limited proteolysis.
• Heavy metal music, a subgenre of rock music.
• Heroes of Might and Magic (more often referred to as HoMM), a series of turn-based strategy games by New World Computing.
• Hidden Markov model, a statistical model.
• Homenmen, an Armenian sporting organization.
• Hum (sound), a sound one makes when thinking, eg. "Hmm, I wonder..."
• Hyundai Merchant Marine, a South Korean logistics company.
• Marine Medium Helicopter Squadrons, United States Marine Corps squadrons that fly the CH-46 Sea Knight helicopter.