The short insult hides an older household compound.
Middle English hus meant house. It joined wif, wife or woman, in huswif. Hussy is an altered form of that compound, with a familiar disparaging use.
The first slot is a selected component, not an older use of the whole word. The earliest cited hussy record is already negative; no neutral first use of that exact spelling is claimed.
Source
Merriam-Webster: hussyThe entry gives alteration of huswif, housewife, from hus, house, and wif, wife/woman, and documents the later negative use.