The Vietnamese word "cứt xu" refers specifically to the feces of a newborn baby. It is a colloquial term that is often used in informal conversations, especially among parents and caregivers when discussing baby care.
In a more advanced context, you might use "cứt xu" when discussing infant health or development, especially when noting changes in a baby’s stool as an indicator of their diet or health status.
While "cứt xu" specifically refers to newborn feces, "cứt" alone can mean feces in general and is used in various contexts to describe animal or human waste.