
Circle, CIRCLE, dot, dot,
now you have a cootie shot.
The Big Bang Theory Season 2, Episode 10

We need to widen our CIRCLE.
The Big Bang Theory Season 1, Episode 1

...in extreme temperatures
such as we will face in the Arctic Circle.
The Big Bang Theory Season 2, Episode 23

I have a very wide CIRCLE.
The Big Bang Theory Season 1, Episode 1

It's the CIRCLE of life, sweetie.
The Big Bang Theory Season 4, Episode 23