PaymentAddress.dependentLocality

The read-only dependentLocality property of the PaymentAddress interface is a string containing a sublocality designation within a city, such as a  neighborhood, borough, district, or, in the United Kingdom, a dependent locality. Also known as a post town.

var paymentDependentLocality = PaymentAddress.dependentLocality;

A DOMString indicating the sublocality portion of the address. This may be an empty string if no sublocality is available or required. It's used to provide disambiguation when a city may include areas that duplicate street names

A sublocality is an area within a city, such as a neighborhood, borough, or district. In the United Kingdom, this is used to indicate the post town in the United Kingdom (known officially by the Royal Mail as the dependent locality). This is a disambiguating feature of addresses in places where a city may have areas that duplicate street names.