- Main Entry:
- war·fa·rin

- Pronunciation:
-
\ˈwȯr-fə-rən\
- Function:
- noun
- Etymology:
- Wisconsin Alumni Research Foundation (its patentee) + coumarin
- Date:
- 1950
: a crystalline anticoagulant coumarin derivative C19H16O4 used chiefly in the form of its sodium salt as a rodent poison and in medicine