Bernadette got her DOCTORATE.
The Big Bang Theory Season 10, Episode 11
What's a world-renowned entomologist
with a DOCTORATE...
The Big Bang Theory Season 3, Episode 2
You've heard him tease me
about not having a DOCTORATE.
The Big Bang Theory Season 5, Episode 21
I've been thinking about getting my DOCTORATE,
and he wants to teach. Why not?
The Big Bang Theory Season 8, Episode 2
I have a DOCTORATE in astrophysics
and I'm every bit as awesome
The Big Bang Theory Season 10, Episode 11