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The prefix "den" comes from the Japanese word "Denki" which means Electricity. Many words use that or the prefix "den" to denote that something is electric. Tatsu is an old Japanese word for Dragon. Japan/China has several words for dragon actually.
Tennis' Spiffy and Mag's Dragohm seem to be top quality choices.
I like names that either are incredibly type based (see: GHOSTEEL) and names that are so random that they absolutely no link to the pokemon whatsoever.
Panzer (a German tank, especially in the context of World War II. Attributively, the term also refers to armoured military forces, as in panzer divisions or panzer battles) + roar
Arg, billymills, I'm glad I decided to scroll up the page one last time and look; I was going to post almost exactly as you did. Spiffy and Dragohm are great, but Thundra also caught my eye.
Ryo/Ryu (Japanese for dragon (duh)) + Biot-Savart. Both have silent t's.
The reference is a bit obscure, but it seems very appropriate, especially if one of the more streamlined designs gets picked. Also, the spelling can be changed to better reflect the pronounciation if people think it necessary.