The term INTERSTATES: ABBR. is an abbreviation for the interstate highways and routes that are found in the United States. The two crossword solutions for this term are HWYS (4 letters) and RTES (4 letters). HWYS stands for highways, which are long roads that connect cities and states. RTES stands for routes, which are shorter roads that connect smaller towns and cities. Both highways and routes are part of the interstate system in the United States.