The phrase "highway mileage" refers to the distance a vehicle can travel on a gallon of fuel while driving on the highway. It tells you how efficiently a car uses gas when driving at higher speeds on the highway. Full definition
Typically, we managed roughly 400 miles between road - trip fill - ups, with an observed highway mileage of about 25 mpg. (automobilemag.com)
Highway mileage in the front - wheel drive model goes up from 28 mpg in the old version to 31 in the new. (Autoweek.com)
But the price you pay for that performance is in fuel economy and a 16 miles per gallon city / 25 mpg highway mileage rating. (articles.orlandosentinel.com)