What does the "moonlike faces" mean in George Orwell's Burmese Days?

In Chapter 14 of George Orwell's Burmese Days, when they went hunting and visited a local village, there is a sentence "In the doorway of every hut clusters of moonlike, rustic faces gaped at the ‘Ingaleikma’(English woman)."

What does the "moonlike face" mean here? As round as the moon? As yellow as the moon? Or someone showing their front faces while others showing their side faces just like the waxing and waning of the moon?

Thanks in advance.