Based on the premise that
"lumen" sounds like "LEMON"?
The Big Bang Theory Season 12, Episode 14
A LEMON one... or any of them.
Game of Thrones Season 1, Episode 9
From now on, "frog" is me, "sandwich"
means you, and "LEMON" means rocket.
The Big Bang Theory Season 6, Episode 3
I usually don't like LEMON bars,
but these are really good.
The Big Bang Theory Season 8, Episode 6
"Examinations of moose chowder
in LEMON parachutes."
The Big Bang Theory Season 12, Episode 9