I completely missed that posts 1 and 2 were both you.
Yep, right there in the beginning, there was the word.
Those circles are homos… 
Not that there’s anything wrong with that.
You were hyp-mo-tized!
Coaxial?
Oh, duh. I didn’t notice you’d answered your own question.
If one circle was inside the other, but they weren’t concentric (i.e. the smaller circle was off-centre relative to the larger one), then I dunno. Superimposed? Or just say the smaller circle is inside the larger one.
Like a circle in a spiral
Like a wheel within a wheel
Never ending or beginning,
On an ever spinning wheel
As the images unwind
Like the circles that you find
In the windmills of your mind.
Also, I am reliably informed that the big wheel is run by faith, while the little wheel runs by the grace of God. However, this only applies if the wheels are both way up in the middle of the air.
My username is my cite.
Nice username/post match!