Possible Clues:

• Having the same midpoint
• This will have you going in circles? Trick by rugby player - briefly, the one caught!
• In the Ehrenstein illusion, a square on ____ circles seems to have curved sides
• Like rings on target
• What Target's rings are
• Like some circles, mostly wealthy after verbal agreement?
• Like some circles
• Like onion rings? Agree with Little Richard, reportedly
• Connect Internet Relay Chat supply with a common centre
• Having a common center