When it comes to overnight shipping, there are plenty of synonyms for the term "next-day air" that you can use depending on your needs. Some of the most popular alternatives include overnight shipping, express delivery, fast shipping, and expedited shipping. These options offer quick and reliable shipping for urgent packages that need to be delivered as soon as possible. Other alternatives to next-day air include same-day shipping, next-day delivery, and two-day shipping, which offer various levels of urgency and cost. No matter what term you prefer, it's important to choose a shipping option that meets your business needs and budget constraints.