WordWeb Online

1. Obstruct access to
   - blockade
    
2. Render unsuitable for passage
   "block off the streets";
   - barricade, block, blockade, stop, block up, bar
    
3. Block off the passage through
   "We block off the valve";
   - shut off, close off

Derived forms: blocking off, blocked off, blocks off

Type of: block, close up, impede, jam, obstruct, obturate, occlude