A thruway is a wide, fast road that goes a long way with no traffic lights and no shops beside it, and that you usually pay to use. You get on at a numbered entrance, drive, and pay at the toll booth. This is American English, and quite regional inside American English: it is most at home in New York State, where the famous road running across the state is called the New York State Thruway. Elsewhere in the United States the same kind of road is called a freeway, an expressway, a turnpike, or an interstate — which name people use depends almost entirely on where they live, not on how the road is built. Notice the spelling: 'thru' is the short, casual American spelling of 'through', the same spelling you see in 'drive-thru'. So thruway means 'the road that goes through', a road for getting through and past places rather than into them. That casual spelling is why you should be careful with it in writing: 'thru' on its own is too informal for school work or a business email. Inside the fixed name Thruway it is normal, because it is a name.

（美）收費高速公路，尤指紐約州那條 Thruway。台灣說的「高速公路」平常對應的是 highway / freeway，不是 thruway。