What are the thin pancakes served with Peking duck called?

The thin pancakes served with Peking duck are commonly called Mandarin pancakes.

These soft, wheat-flour wrappers are designed to hold slices of roast duck along with sweet bean sauce, cucumber, and strips of scallion. They are usually steamed or cooked briefly on a griddle, producing thin, pliable rounds rather than the fluffy breakfast pancakes familiar in Western cuisine. A traditional preparation often rolls two dough rounds together with oil between them, then separates them after cooking.

In Mandarin, the wrappers may be called bao bing, meaning “thin pancake,” and they are also associated with chun bing, or spring pancakes. “Mandarin pancakes” is the established English name commonly used for the Peking-duck accompaniment. They are sometimes confused with spring-roll wrappers, but spring-roll wrappers are generally thinner, more brittle, and intended to be fried after filling.

Peking duck is served with more than just the pancakes. In a classic presentation, the chef carves the duck at the table, and diners assemble each bite with crisp skin or meat, sauce, scallion, and cucumber. Some restaurants instead serve steamed buns, but those are a different wrapper.