Source : WordNet®

block off
     v 1: obstruct access to [syn: {blockade}]
     2: render unsuitable for passage; "block the way"; "barricade
        the streets"; "stop the busy road" [syn: {barricade}, {block},
         {blockade}, {stop}, {block up}, {bar}]
     3: block off the passage through [syn: {shut off}, {close off}]