
I went to school for half my life.
I have a DOCTORATE.
The Big Bang Theory Season 8, Episode 20

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

I have a DOCTORATE in astrophysics
and I'm every bit as awesome
The Big Bang Theory Season 10, Episode 11

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

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