View source for H3

{{wiktionary}}
'''H3''', '''H03''' or '''H-3''' may refer to:
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== Entertainment ==

* [[H3 (film)|''H3'' (film)]], a 2001 film about the 1981 Irish hunger strike
* ''[[H3 – Halloween Horror Hostel]]'', a 2008 German horror-parody television film
* ''[[Happy Hustle High]]'', a manga series by Rie Takada, originally titled "H3 School!"
* [[h3h3Productions]], styled "[h3]", a satirical YouTube channel

== Science ==

* [[Triatomic hydrogen]] (H<sub>3</sub>), an unstable molecule
* [[Trihydrogen cation]] ({{chem2|H3+}}), one of the most abundant ions in the universe
* [[Tritium]] (<sup>3</sup>H), or hydrogen-3, an isotope of hydrogen
* [[ATC code H03]] ''Thyroid therapy'', a subgroup of the Anatomical Therapeutic Chemical Classification System
* [[British NVC community H3]], a heath community of the British National Vegetation Classification system
* [[Histamine H3 receptor|Histamine H<sub>3</sub> receptor]], a human gene
* [[Histone H3]], a component of DNA higher structure in eukaryotic cells
* [[Hekla 3 eruption]], a huge volcanic eruption around 1000 BC

== Computing ==

* [[HTTP/3]], the third major version of the Hypertext Transfer Protocol
* [[Socket H3]], a CPU socket
* {{tag|h3|content=}}, the level-3 [[HTML element#heading|HTML heading markup element]]

==Transportation==

===Air and space===
* [[H3 (rocket)]], a Japanese expendable launch system
* [[H-3 Air Base]], a former Iraqi Air Force base in western Iraq
* [[Dynali H3 EasyFlyer]], a Belgian helicopter
* [[Howland H-3 Pegasus]], an American ultralight aircraft
* [[Sikorsky SH-3 Sea King]], an American twin-engined anti-submarine warfare helicopter
* [[Standard H-3]], an early American reconnaissance aircraft
* [[VFW-Fokker H3 Sprinter]], a West German experimental rotorcraft

===Automobiles===
* [[Brilliance H3]], a Chinese compact sedan
* [[Great Wall Haval H3]], a Chinese compact SUV
* [[Huansu H3]], a Chinese compact MPV
* [[Hummer H3]], an American mid-size SUV
* [[IFA Horch H3]], an East German lorry
* [[Rely H3]], a Chinese light commercial van

===Rail===
* [[Alstom Prima H3]], a French diesel/battery hybrid locomotive
* [[GNR Class H3]], a class of British steam locomotives
* H3 series of [[METRORail#H3 series|METRORail]] tramways in Houston

===Roads===
* [[H3 Monks Way]], part of the Milton Keynes grid road system, United Kingdom
* [[Interstate H-3]], a highway in Hawaii

===Ships===
* [[H3 (yacht)|''H3'' (yacht)]], a luxury yacht
* {{HMS|Grenville|H03}}, a destroyer of the British Royal Navy
* {{HMS|H3}}, a submarine of the British Royal Navy
* {{USS|H-3|SS-30}}, a submarine of the United States Navy

== Other uses ==
* [[H3 (classification)]], a para-cycling classification
* [[H3 (Kuwait)]], an archaeological site
* [[H3 (pyrotechnics)]], a pyrotechnic composition
* {{lang|ine-x-proto|[[*h3|*h₃]]|proto=no}}, one of the three laryngeals in the reconstructed Proto-Indo-European language
* [[H3 Entertainment]], a subsidiary of the film industry company The H Collective
* ''[[H3 Podcast]]'', hosted by Ethan Klein
* [[Gerovital H3]], a pseudoscientific anti-aging treatment
* [[Hash House Harriers]], an international group of non-competitive running, social and drinking clubs
* H3, an 18th-century marine chronometer by [[John Harrison#The first three marine timekeepers|John Harrison]]
* H3, a type of [[List of automotive light bulb types|automotive halogen lamp]]
* H3 Hardy Collaboration Architecture, a firm started by [[Hugh Hardy]]
* DSC-H3, a 2008 [[List of Sony Cyber-shot cameras#H series|Sony Cyber-shot]] camera

== See also ==
{{canned search|h3}}
* [[3H (disambiguation)]]
* [[HHH (disambiguation)]]
* [[Triple H (disambiguation)]]

{{Letter-Number Combination Disambiguation}}