
All right. Let's BUCKLE down and work.
The Big Bang Theory Season 3, Episode 4

Well, then, BUCKLE up.
You're in for a cranky night.
The Big Bang Theory Season 8, Episode 20

the National Belt Buckle Collectors
meet-and-greet.
The Big Bang Theory Season 10, Episode 19

Well, then, BUCKLE up.
The Big Bang Theory Season 1, Episode 4

It said right there on the invitation,
"Buckle up for fun!"
The Big Bang Theory Season 10, Episode 19