
Is "back on track" a HINT
that it has something to do with trains?
The Big Bang Theory Season 10, Episode 11

Do I detect a HINT of condescension?
The Big Bang Theory Season 4, Episode 3

Hint: it's based
on Sanskrit,
The Big Bang Theory Season 12, Episode 2

Hint: it's a cube of a cube
of a prime.
The Big Bang Theory Season 12, Episode 23

Hint: He and Darth Vader
are tied for number two.
The Big Bang Theory Season 3, Episode 15