Antibiotics are chemical products or derivatives of certain organisms that inhibit the growth of or destroy other organisms. The term “antibiotic” (from the Greek anti, meaning “against,” and biosis, meaning “life”) refers to its purpose in destroying a life form. In 1889 Paul Vuillemin (1861–1932) used the term “antibiosis” to describe bacterial antagonism. He had isolated pyocyanin, which inhibited the growth of bacteria in test tubes but was too lethal to be used in disease therapy. In was not until the mid–1940s that Selman Waksman (1888–1973) used the term “antibiotic” to describe a compound that had therapeutic effects against disease.