The distinction between organic and inorganic carbon compounds, while useful in organizing the vast subject of chemistry... is somewhat arbitrary. Organic chemistry is the science concerned with all aspects of organic compounds. Organic synthesis is the methodology of their preparation.
No, it is not possible to contract the typical STDs, such as syphilis, gonorrhea, chlamydia, hepatitis B, etc. from wearing someone else's dirty underwear. However crabs and scabies, may be spread in this fashion.
Underwear may also be used to preserve the wearer's modesty â for instance, some women wear camisoles and slips (petticoats) under clothes that are sheer. Conversely, some types of underwear can be worn for sexual titillation, such as edible underwear, crotchless panties and thongs.