"D/D/D" stands for Different Dimension Daemon. Taste the power of demon kings that have conquered different dimensions.— Declan Akaba on the D/D/D.
"D/D/D" monsters are named after either a historical person, usually a military leader, or some form of the end of the world (e.g. "Armageddon") and they encompass all of the Extra Deck Summon Monsters as well as some Main Deck Effect Monsters. Most of them have an attributed office role from a pun on their name, creating a demonic hierarchy-themed archetype.
Each of the "Super Doom King" monsters are based on past main antagonists from previous series.
- Purple Armageddon: Zorc Necrophades and Nightshroud.
- Bright Armageddon: Z-one
- Dark Armageddon: Don Thousand and the Barian Emblem that serves as his symbol.
- Its Japanese name - "Darkness Hell Armageddon" - is the same as Nightshroud's Japanese name; Darkness.
According to Declan Akaba, "D/D/D" is short for "Different Dimension Demon" (ディファレント・ディメンション・デーモン Difarento Dimenshon Dēmon).  This refers to how the "D/D/D" monsters consists of monsters of all Extra Deck Summoning methods, with each Extra Deck Summoning method existing during the ARC-V series (Fusion, Synchro, and Xyz) originating from a different dimension in the anime.
The "D/D/D" archetype marks the first time that monsters with the word "Demon" (or "Daemon") in their names were released in the TCG, with said word intact. However since the word "Demon" is simply represented in the card names via an acronym, the use of this word is comparatively subtle, and the English anime does not have Declan mention this detail.