Black lace mini length nightgown from the 90s with spaghetti straps. It's 2 layers with a layer of silky black nylon under the lace. I personally wore pieces like this as a dress in the 90s but even with 2 layers it's not 100% opaque.
Brand - The Woman Within - Fifth Avenue
Content - Lace - 100% Polyester, Lining - 100% Nylon
Size - Labeled Size A2 - approximately a modern Small but check all measurements to ensure fit
Chest - 17" pit to pit
Waist - approximately 17.5" across
Hips - approximately 19.5" across
Length - 33.75"
Condition - I don't see any flaws