Wordnet 3.0
NOUN (1)
1. 
 a procession (of wagons or mules or camels) traveling together in single file; 
- Example: "we were part of a caravan of almost a thousand camels"- Example: "they joined the wagon train for safety"[syn: caravan, train, wagon train]
WordNet (r) 3.0 (2006):
wagon train
    n 1: a procession (of wagons or mules or camels) traveling
         together in single file; "we were part of a caravan of
         almost a thousand camels"; "they joined the wagon train for
         safety" [syn: caravan, train, wagon train]