Adjuvant

adjuvant
\AJ-uh-vuhnt\ , adjective, noun:
1.
Serving to help or assist; auxiliary.
2.
Assisting in the prevention, amelioration, or cure of disease.
noun:
1.
A person or thing that aids or helps.
2.
Anything that aids in removing or preventing a disease, esp. a substance added to a prescription to aid the effect of the main ingredient.