WordNet (r) 3.0 (2006):
close off v 1: stem the flow of; "shut off the gas when you leave for a vacation" [syn: shut off, close off] 2: isolate or separate; "She was shut off from the friends" [syn: shut off, close off] 3: block off the passage through; "We shut off the valve" [syn: shut off, block off, close off]