'Interstate' definitions:

Definition of 'interstate'

(from WordNet)
adjective
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]
noun
One of the system of highways linking major cities in the 48 contiguous states of the United States [syn: interstate, interstate highway]

Definition of 'Interstate'

From: GCIDE
  • Interstate \In"ter*state`\, a. Pertaining to the mutual relations of States; existing between, or including, different States; as, interstate commerce. --Story.

Definition of 'interstate'

From: GCIDE
  • interstate \in"ter*state`\, n. An interstate highway, part of the United States Interstate Highway system. [PJC]