
From now on, "frog" is me, "sandwich"
means you, and "LEMON" means rocket.
The Big Bang Theory Season 6, Episode 3

He knew you liked LEMON cakes.
Game of Thrones Season 4, Episode 5

Lemon cakes?
Game of Thrones Season 4, Episode 1

and you go suck a LEMON?
The Big Bang Theory Season 5, Episode 17

Based on the premise that
"lumen" sounds like "LEMON"?
The Big Bang Theory Season 12, Episode 14