
Your DOCTORATE is in neurobiology.
I fail to see the distinction.
The Big Bang Theory Season 4, Episode 24

You've heard him tease me
about not having a DOCTORATE.
The Big Bang Theory Season 5, Episode 21

What's a world-renowned entomologist
with a DOCTORATE...
The Big Bang Theory Season 3, Episode 2

I have a DOCTORATE
from Indiana University.
The Big Bang Theory Season 12, Episode 5

SHELDON: Go ahead.
That's the only DOCTORATE you'll ever get.
The Big Bang Theory Season 6, Episode 9