cover-slut

noun2

1. •
   (no longer used) An apron or pinafore, worn to hide slovenliness (such as dirt, stains, or tears) in the clothing beneath.

   • Nor let your women there appear / With dirty smock-sleeves, foul head-geare, / With Cover-slut from Neck to Toe, / As Maids to morning Lectures go. — 1678
2. •
   (figurative, no longer used) Any surface appearance hiding something underneath.

   • Fie, madam, you'll ruin the sex! Husband, say ye? A mere thing—a cover-slut of custom! — 1690