
He didn't remember me, because the last
time we met I was in a Halloween COSTUME.
The Big Bang Theory Season 2, Episode 14

in the top half of
a Chewbacca COSTUME.
The Big Bang Theory Season 5, Episode 7

...except everybody's wearing
the same COSTUME: Indian Guy.
The Big Bang Theory Season 4, Episode 7

Yeah, now about those.
They came from a COSTUME shop...
The Big Bang Theory Season 8, Episode 22

"Where's your COSTUME?
Why are you wearing work clothes?"
The Big Bang Theory Season 6, Episode 5