
...I want to have COITUS with Amy.
The Big Bang Theory Season 8, Episode 1

you haven't had COITUS on?
The Big Bang Theory Season 7, Episode 18

And she found atomic spectroscopy boring.
I wouldn't COITUS her with your genitals.
The Big Bang Theory Season 9, Episode 8

I find the concept of COITUS ridiculous
and off-putting.
The Big Bang Theory Season 6, Episode 20

Also, if they did have COITUS, we'll
all be needing a skilled psychiatrist.
The Big Bang Theory Season 10, Episode 1