The Vietnamese pronoun 'chị' is used when referring to or addressing an older female individual. In Vietnamese culture, it is important to show respect to elders, so this pronoun is commonly used when engaging with an older female to demonstrate respect or familial connection. 'Chị' acts in a similar way to the English 'sister' when used within a family context, but its expression is broader in that it can be used for non-family members as well.