I'm making a BUR and this is related to it. I can't seem to find any past discussion on this.
The wiki says
Lingerie traditionally refers to underwear worn by women.
Please take note that lingerie is a bit more than just wearing a set of plain white bra and panties; the name implies that the garments are special or otherwise fancier than your everyday undergarments. Typically the design will be more exotic/risqué, or is made out of special fabrics (generally speaking silk).
Is there any reason why lingerie wouldn't be underwear, since underwear includes both bra and panties?