What type of explosive is RDX?
RDX, abbreviation of Research Department eXplosive or Royal Demolition eXplosive, formally cyclotrimethylenetrinitramine, also called cyclonite, hexogen, or T4, powerful explosive, discovered by Georg Friedrich Henning of Germany and patented in 1898 but not used until World War II, when most of the warring powers ...
RDX | explosive | Britannica.com
What is the full name of RDX?
For security reasons, Britain termed cyclonite as "Research Department Explosive" (R.D.X.). The term RDX appeared in the United States in 1946.