frau
n. countable C1 Advanced US //ˈfɹaʊ// frau
n. a title for a German-speaking woman, similar to 'Mrs.' or 'Ms.' in English. It is also used as a polite way to address a woman in a German-speaking country.
n. a German title of address for a woman, equivalent to 'Mrs.' or 'Ms.'. When used in English contexts, it often refers specifically to a married woman or a woman of German nationality.
The hotel clerk addressed her as Frau Schmidt.
During the conference in Berlin, the moderator introduced the keynote speaker as Frau Professor Weber.
From German Frau.
Usage
In modern German, it is the standard polite address for all adult women regardless of marital status; in English usage, it often retains a more traditional association with married women.