Definition of "closing off" []

• The act of isolating something; setting something apart from others (noun)

WordNet. Princeton University. 2010.

• "Then Thebe Under Plakos can be taken, closing off the routes through the Ida mountains and preventing the coming of reinforcements from the Fat King, Kygones, in Lykia and others friendly to Troy.”"
• "On March 29, Clinton sent picked troops in flatboats across the Ashley River to occupy part of the peninsula on which Charleston sat, thus closing off any retreat to the west."