'Threshing floor' in the Bible

and now, is not Boaz of our acquaintance, with whose young women thou hast been? lo, he is winnowing the threshing-floor of barley to-night,

and thou hast bathed, and anointed thyself, and put thy garments upon thee, and gone down to the threshing-floor; let not thyself be known to the man till he complete to eat and to drink;

And she goeth down to the threshing-floor, and doth according to all that her mother-in-law commanded her