
They exist in case we ever make contact
with an alien CIVILIZATION.
The Big Bang Theory Season 9, Episode 10

Rode them from Valyria
to build the greatest CIVILIZATION
Game of Thrones Season 1, Episode 4

we're gonna have to
rebuild CIVILIZATION.
The Big Bang Theory Season 12, Episode 14

could be evidence
of alien CIVILIZATION.
The Big Bang Theory Season 12, Episode 20

And what a CIVILIZATION is the Greeks'.
The Big Bang Theory Season 4, Episode 21