Sheldon, you can't train my girlfriend
like a lab RAT.
The Big Bang Theory Season 3, Episode 3
The difference between us and the RAT...
The Big Bang Theory Season 1, Episode 5
So, I'm like a lab RAT
before your real friends come over?
The Big Bang Theory Season 10, Episode 6
Getting his pet RAT a reward
Game of Thrones Season 3, Episode 7
a snitch, a filthy RAT.
Money Heist Season 1, Episode 6