Wordnet 3.0
VERB (1)
1. 
 belong to an earlier time; 
- Example: "This story dates back 200 years"[syn: go back, date back, date from]
WordNet (r) 3.0 (2006):
date back
    v 1: belong to an earlier time; "This story dates back 200
         years" [syn: go back, date back, date from]