frau (n.) Look up frau at Dictionary.com
"married woman," 1813, from German Frau "woman, wife," from Middle High German vrouwe "lady, mistress," from Old High German frouwa "mistress, lady" (9c.), from Proto-Germanic *frowo "lady" (source also of Old English freo "woman, lady," Middle Dutch vrouwe, Dutch vrouw), fem. of *frawan "lord," from suffixed form of PIE *pro- (see pro-). Swedish fru, Danish frue are ultimately from Dutch; the proper Scandinavian form is preserved in Old Norse freyja "lady," husfreyja "mistress of the house."