Glossary WW1 Glossary A B C D E F G H I J K L M N O P Q R S T U V W Y Z There are 12 names in this directory beginning with the letter H.HA Heavy ArtilleryHAR Heavy Artillery ReserveHBMGC Heavy Branch Machine Gun Corps (later Tank Corps)HDMHull Daily MailHE High ExplosiveHMSHer Majestys ShipHMTHer Majestys TrawlerHPD Home Postal DepotHS Home ServiceHSC Hospital Ship Case (medical)HT Horse TransportHV High Velocity