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HAC: Honourable Artillery Company.
HAG: Heavy Artillery Group.
Hairy: Large British transport horse.
Halberstadt C-Types: Series of armed German reconnaissance biplanes used during the later war.
Halberstadt CL-Types: Series of German armed reconnaissance/ground attack aircraft used from 1917.
Halberstadt D-Types: Series of German fighter biplanes.
Handelskrieg : ‘Trade Warfare’, a German term for their targeting of non-military shipping by naval craft and submarines in an attempt to damage their enemies economically.
Handley Page 0/100: British twin-engined bomber used from November 1916.
Handley Page 0/400: An improved version of the Handley Page 0/100 bomber in active service during 1918.
Handley Page V/1500: Britain’s biggest aircraft of the war, it was a long range bomber intended to attack German soil, but was too late to see active service.
Hannover CL-Types: Series of German armed reconnaissance/ground attack aircraft used during 1918.
Hans Wurst : ‘Hans Sausage’, German nickname for a soldier.
Hanriot HD-1: French built fighter plane used largely by Italy and Belgium.
Hansa- Brandenburg C-I: German designed armed reconnaissance plane used by Austria-Hungary.
Hansa- Brandenburg CC: German designed flying fighter boat also used by Austria Hungary.
Hansa- Brandenburg D-I: German designed fighter biplane built and used by Austria-Hungary during 1916-17.
Hansa- Brandenburg KDW: Floating version of the Hansa- Brandenburg D-I.
Hansa- Brandenburg W-12: German armed reconnaissance floatplane used from 1917.
Hansa- Brandenburg W-29: German floatplane used for attack and escort duties from late 1917.
Hard Tack: A soldier’s army biscuit.
Harry: Slang for either the RE8 aircraft or a plate.
Hate: A bombardment.
Hauptmann : German army captain.
Havelock: A covering for the neck on a cap.
Havildar : Indian sergeant of infantry.
Havildar-Major : Indian sergeant-major of infantry.
HE: High explosive.
Heine: American nickname for Germans.
HF: Home Forces.
High Command: The heads of the German Army.
High Seas Fleet: The main battle unit of the German Navy, numbering 27 ships.
Hindenburg Line: A connected series of German defensive fortifications on the Western Front behind which German forces withdrew in the winter of 1916-17.
Hindenburg Programme: The virtual economic and social dictatorship established by the German Third Supreme Command in 1916 in order to organise and increase production for military ends.
HKK: Höheren Kavallerie-Kommandeure, German cavalry corps.
HMG: His Majesty’s Government.
HMS: His Majesty’s Ship.
Home Front(s) : The civilian aspect of war.
Homforty: Nickname for the French goods railway wagon.
hommes / les hommes : ‘the men’, French soldiers reference to themselves.
hommes des troupes : A reference to everyone in the French army who wasn’t an officer.
Honved: The Hungarian Landwehr, their territorial army.
Hop the Bags: To climb over the trench parapet and attack.
Horse-length: In imperial measurements eight feet.
Horse-lines: The site of draught animals.
Horse-Width: In imperial measurements three feet.
Hospital Blues: The uniform worn by British soldiers in hospital or convalescent homes.
Hotchkiss Gun: The main machinegun of the French army throughout the war.
House / Housey-Housey: The game Bingo.
Housewife: Small container/pouch with sewing equipment.
Howitzer: Artillery piece with a high ‘lobbing’ trajectory.
Hun: Allied slang for Germans.
Huntley and Palmer: Colloquial name for the twin Lewis guns mounted on aircraft, derived from a biscuit manufacturer!
Hush-hush: To do with secrets or intelligence information.
Hypo: sodium thiosulphate, anti-gas.