HM or hm may refer to:

Arts and entertainment

* ''HM'' (magazine), a Christian hard rock magazine * Hidden Machine, a type of item in Pokémon

Businesses

* H&M, a Swedish clothing company * Hindustan Motors, an automobile manufacturer of India *

Air Seychelles Air Seychelles is the national airline of the Republic of Seychelles. Its head office is located at Seychelles International Airport on the island of Mahé and it operates inter-island and international flights and charter flights. History E ...

(IATA airline code)

Other uses

* Heard Island and McDonald Islands (ISO 3166 digram and FIPS PUB 10-4 territory code) **

.hm .hm is the Internet country code top-level domain ( ccTLD) of the Heard and McDonald Islands, uninhabited islands in the southern Indian Ocean under the sovereign control of Australia. Although .hm gets a small amount of use, Australia uses the ...

, the Internet country code top-level domain ostensibly for the above * Hectometre, hm, an SI unit of length *

Henry Molaison Henry Gustav Molaison (February 26, 1926 – December 2, 2008), known widely as H.M., was an American who had a bilateral medial temporal lobe, temporal lobectomy to surgically resect the anterior two thirds of his Hippocampus, hippocampi, p ...

, aka Patient H.M., a man with anterograde amnesia * His or Her

Majesty Majesty (abbreviated HM for His Majesty or Her Majesty, oral address Your Majesty; from the Latin ''maiestas'', meaning "greatness") is used as a manner of address by many monarchs, usually kings or queens. Where used, the style outranks the st ...

, a form of address for various monarchs * Hindley–Milner type system, in mathematics * Hospital corpsman, in the United States Navy * Sisters of the Holy Humility of Mary's postnominal initials {{disambiguation