About 5-6 years ago I found out that "Dokku" means something like "crappy" in Telugu (I think). Lots of people seem to refer to it when talking about politics, theaters, and methods of transportation on twitter.
It's also the name of some famous Korean actor's Dog (I think they got the name from a Naruto character named Dokku). The dog is fairly new, and lots of folks stanning particular actors or actresses on twitter use the word `dokku` in their username.
Dokku Umarov was also a Chechen mujahid in both Chechen wars. References to him pop up every so often (he died in 2013, _just_ after the Dokku project started).
IIRC the name "Dokku" is a portmanteau of `Docker` and `Heroku`. How you pronounce it is up to you, though it seems I pronounce it very differently from others (I use "dough" instead of "dah").
Finally, "Dooku" is not how it's spelled, though lots of people seem to refer to Count Dokku of Star Wars fame :D