
I had lost a lot of THUMB blood.
The Big Bang Theory Season 5, Episode 16

If I wanted to, I could wipe it out
with my THUMB like a god.
The Big Bang Theory Season 6, Episode 21

that's the Pasadena City Police, but if
you broke my left THUMB, that's the FBI.
The Big Bang Theory Season 9, Episode 14

No. But your THUMB does.
The Big Bang Theory Season 5, Episode 16

You know,
Italian housewives have a rule of THUMB:
The Big Bang Theory Season 2, Episode 9