Oh, Hivemind? Are You There?

Years ago, I read a novel by Robert Silverberg called The World Inside. The setting was a far future of Earth on which individual, sprawling cities had disappeared, replaced by what he called "urban monads," monstrous, completely self-contained, single structures housing hundreds of thousands of people each. His main character lived in the Chi-Pitt urban monad (or maybe it was a constellation of urban monads), located in a roughly oval-shaped space between where the old cities of Chicago and Pittsburgh once existed. People were born, lived their entire lives, and died without ever leaving their 'urbmon.'

They towered into the sky (and perhaps into the earth, as well) and were self-contained human Habitrails with everything a person would need to sustain them for their entire lives: farms, shopping, offices, homes, recreation...it was all there, inside the urbmons.

I have a story set in a similar (but ultimately darker) future, and I want to call these buildings something like 'urban monad' but I don't want to use the phrase 'urban monad.' I want something futuristic-sounding, but not clunky.

My character mentions that his allotted space of 2000 cubic feet (10'w x 10'd x 20'h) is called an Ikea, but the reasons why are lost in the murk of time. So I'm not averse to doing something along those lines if it'll draw a chuckle from the reader. But I don't want to use 'urban monad' because, although this story is in many ways an homage to Silverberg's novel, I don't want to just steal his terminology. Unfortunately, all I can think of is 'urban monad' and 'urbmon.'

To further the homage, my character lives in the Nashlantaham [constellation?] of [word I'm looking for]s, because it exists (roughly) within the triangular area formed if you connect the old cities of Nashville, Birmingham, and Atlanta with straight lines. That can change, of course, but I had to come up with a name. :)

Any ideas what to call these gigantic structures?