Wordnet 3.0
NOUN (1)
1. 
 someone who moves or passes across; 
- Example: "the traversers slowly ascended the mountain"
The Collaborative International Dictionary of English v.0.48:
Traverser \Trav"ers*er\, n.
   1. One who, or that which, traverses, or moves, as an index
      on a scale, and the like.
      [1913 Webster]
   2. (Law) One who traverses, or denies.
      [1913 Webster]
   3. (Railroad) A traverse table. See under Traverse, n.
      [1913 Webster]
WordNet (r) 3.0 (2006):
traverser
    n 1: someone who moves or passes across; "the traversers slowly
         ascended the mountain"