<human>:  I have a question about a recipe for Chicken and Broccoli Pasta. What is the difference between a scallion and a spring onion?
<bot>: A scallion is a young green onion, while a spring onion is a young green onion that has been allowed to grow to full size. Spring onions are usually used in salads and stir-fries, while scallions are used in soups, stews, and stir-fries.