Air-express is a term commonly used to describe a service that offers fast and efficient delivery of goods or packages through air transportation. However, if you're looking for synonyms for the word air-express, there are several options you can use instead. For instance, you can use the term 'air cargo' to describe the transportation of goods by air. Other alternatives like 'air freight,' 'air transportation,' and 'air delivery' also work well. Additionally, 'air courier' is another synonym that describes the same process of delivering packages or documents through air transportation. No matter the term you use, air-express, air cargo, air freight, or air courier, they all have the same goal of quick and efficient delivery of packages to their destinations through air transport.