Is the correct term for this lingerie a "teddy"? That seems to be what they're called nowadays. Sorry for the floor shots, but for identification purposes, it shows off the shape of the garment better. The lack of seam finishes (some pinked, some straight cut) and the diamond gusset are telling me vintage. Also, the gusset has a button closure using two shell buttons. The ribbon shoulder straps are non-adjustable. Am I way off in thinking 30s/40s? It has a fabric content tag but no other tags (what is "weighted" silk?). Thank you for any input!