Wordnet 3.0
VERB (2)
1. 
 secure with or as if with ropes; 
- Example: "tie down the prisoners"- Example: "tie up the old newspapers and bring them to the recycling shed"[syn: tie down, tie up, bind, truss]
2.  restrain from independence by an obligation; 
- Example: "He was tied down by his work"
WordNet (r) 3.0 (2006):
tie down
    v 1: secure with or as if with ropes; "tie down the prisoners";
         "tie up the old newspapers and bring them to the recycling
         shed" [syn: tie down, tie up, bind, truss]
    2: restrain from independence by an obligation; "He was tied
       down by his work"