
I've extended a friendly,
CASUAL greeting.
The Big Bang Theory Season 3, Episode 10

You're the one who wanted
to keep things CASUAL.
The Big Bang Theory Season 11, Episode 8

Is there some new kind of Casual Friday
I don't know about?
The Big Bang Theory Season 2, Episode 5

I'm striking up a CASUAL conversation
with you.
The Big Bang Theory Season 2, Episode 9

...to provide Amy with conversation
and CASUAL physical contact.
The Big Bang Theory Season 6, Episode 1