hay bag

A dated, derogatory slang term for a woman, particularly one viewed as slovenly, unattractive, or worn-out. It's the kind of old-fashioned insult that pops up in classic crime fiction or early 20th century American slang. In its literal sense it's just a bag of hay for feeding horses, but the slang usage reduces a woman to something similarly unglamorous. Today it's largely obsolete outside of period settings, but worth knowing for context.