Originally referring to a kind of bread soup made with soured milk. Hence from a variant of Middle High German brocke (“broken-off piece, especially of bread”) or the verb brocken (“to break into pieces”); compare German Brocken, brocken, Dutch brok. If the -ch- is old, it may be due to hypercorrection (during the interaction of Frankish and High German influences), otherwise it may be a later adaptation to the related Luxembourgish briechen (“to break”), Broch (“fracture”). The feminine gender probably from Mëllech (“milk”) and/or Zopp (“soup”), perhaps from an underlying compound *Brachmëllech, *Brachzopp, the former of which is attested in adjacent dialects in Germany.
Brach m pers or f
The feminine surname is indeclinable.