belt up
Intermediate (B1)informal
Either 'be quiet!' or 'put on your seatbelt!'
"The teacher told the noisy students to belt up and get on with their work."
Hear it in context
REVEALED Semi-Finalists for Live Show 2 | BGT 2026
Britain's Got Talent · 34:07
Hold that belt up again.
Best of Anna Kendrick: Mr Right VS Pitch Perfect | Big Screen Laughs
Big Screen Laughs · 10:09
How high is your belt up?
Fully Rebuilt Mk4 R32 Engine Install
HumbleMechanic · 7:57
So, it pulls the belt up, which means this is not the right serpentine belt.