To cordon off is to close an area with a barrier so nobody may enter. Cordon off the street.
It preserves a scene as much as it protects the public, which is why it goes up so wide. To cordon off an area is easier than to shrink one once people have gathered outside it.
1phrasecordon offTo close an area with a barrier so nobody may enter.
“Police had to cordon off the whole square by nine.”
cordon off is a phrase.
Practised in Phrasal Verbs