Serum

Serum may refer to:

Biology

serum (blood), plasma from which the clotting proteins have been removed
- Antiserum, blood serum with specific antibodies for passive immunity
Serous fluid, any clear bodily fluid
Any drug derived from an animal's blood or serous fluid
Truth serum, a general term for a drug that is likely to make people tell truth or give information
A word for lotion in the cosmetics market