1. 
[syn: interstate, interstate highway]
ADJECTIVE (1)
1.  involving and relating to the mutual relations of states especially of the United States; 
- Example: "Interstate Highway Commission"
- Example: "interstate highways"
- Example: "Interstate Commerce Commission"
- Example: "interstate commerce"
The Collaborative International Dictionary of English v.0.48:
Interstate \In"ter*state`\, a.
   Pertaining to the mutual relations of States; existing
   between, or including, different States; as, interstate
   commerce. --Story.
The Collaborative International Dictionary of English v.0.48:
interstate \in"ter*state`\, n.
   An interstate highway, part of the United States Interstate
   Highway system.
   [PJC]
WordNet (r) 3.0 (2006):
interstate
    adj 1: involving and relating to the mutual relations of states
           especially of the United States; "Interstate Highway
           Commission"; "interstate highways"; "Interstate Commerce
           Commission"; "interstate commerce" [ant: intrastate]
    n 1: one of the system of highways linking major cities in the
         48 contiguous states of the United States [syn:
         interstate, interstate highway]