Yes and no, but mostly yes.

A scallion is a variety of onion in its own right, but so many people call immature green onions scallions that it would be too hard and is much too late to fix it.

A scallion is a member of the white onion family with green on top and white on the bottom. The most visible difference from baby green onions, baby leeks, and baby shallots (with which they really should not be confused) is that the sides of the white base of scallions are essentially straight, where the others are beginning to curve into the development of bulbs. Green onions are simply immature onions picked before their bulbs develop.

Both the white bottom and the green leaves of scallions (which are hollow like chives) can be eaten, either raw or cooked. Scallions have a somewhat milder flavor than green onions.

We know people in the specialty produce business (who know a lot!) who would disagree with us that there is a difference between scallions and green onions, but it just can't be helped....