cordon

Concise Oxford English Dictionary © 2008 Oxford University Press:
cordon /ˈkɔːd(ə)n/

▶noun

• 1 a line or circle of police, soldiers, or guards preventing access to or from a place.

• 2 a fruit tree trained to grow as a single stem.

• 3 Architecture another term for string course.

▶verb (cordon something off) prevent access to or from a place by means of a cordon.

– origin ME: from Ital. cordone, augmentative of corda, and Fr. cordon, dimin. of corde, both from L. chorda (see cord).