HM may refer to:* Hadi Motaharian, is brevity of Hadi Motaharian and alias for he Heavy metals, higher atomic weight metallic elements Horace Mann School, private school in New York City Hollow Metal, an abbreviation often used in architectural schedules for doors Hannah Montana, a popular Disney Channel TV show Haunted Mansion, a dark ride attraction in several Disney theme parks HM (patient), pseudonym of a man with anterograde amnesia (also written H.M.) HM (magazine), a Christian Hard… (More on Hm)