Merriam-Webster Collegiate Dictionary - physic

 I. noun  Etymology: Middle English physik natural science, art of medicine, from Anglo-French phisique, fisik, from Latin ~a, singular, natural science, from Greek physike, from feminine of physikos — more at ~s  Date: 14th century  1.  a. the art or practice of healing disease  b. the practice or profession of medicine  2. a medicinal agent or preparation; especially purgative  3. archaic natural science  II. transitive verb  (~ked; ~king)  Date: 14th century  1. to treat with or administer medicine to; especially purge  2. heal, cure