A nobel laureate coined this word “to avoid the repetition of the rather cumbersome phrase ‘mould broth filtrate’
On the January 20, 2026 episode of Jeopardy, the Final Jeopardy category was “Scientific Words”. Contestants were presented with a clue rooted in the history of medical science and linguistic innovation:
“A Nobel laureate coined this word ‘to avoid the repetition of the rather cumbersome phrase mould broth filtrate’.”
The clue required a deep understanding of both the history of antibiotic development and the evolution of scientific terminology. The correct response, in classic Jeopardy format, was:
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What is penicillin?
The word penicillin was coined by Scottish bacteriologist Alexander Fleming, who discovered the antibiotic properties of the Penicillium mold in 1928. At the time, while working at St. Mary’s Hospital in London, Fleming noticed that a Petri dish containing Staphylococcus bacteria had been contaminated by a blue-green mold, and that the area around the mold was free of bacteria. This mold turned out to be from the genus Penicillium.
Rather than repeatedly refer to the active agent as “mould broth filtrate,” Fleming introduced the name penicillin to describe the substance secreted by the mold that was inhibiting bacterial growth. His decision to use a single word made communication more efficient and highlighted the significance of the discovery. The word combines Penicillium with the suffix -in, commonly used in chemical nomenclature.
Fleming’s Nobel-Winning Discovery
Fleming’s discovery of penicillin marked a turning point in modern medicine. However, it would take more than a decade for the antibiotic to be developed for mass production and widespread clinical use. In the early 1940s, a team at the University of Oxford—including Howard Florey and Ernst Boris Chain—succeeded in purifying penicillin and demonstrating its effectiveness in treating bacterial infections.
In 1945, Alexander Fleming, along with Florey and Chain, was awarded the Nobel Prize in Physiology or Medicine for their work. The naming of penicillin played a critical role in standardizing the substance as a therapeutic agent and helped propel it into the medical mainstream. The word itself is now synonymous with the antibiotic era and the fight against infectious disease.
Scientific Naming and Practical Simplicity
Fleming’s choice to simplify a complex scientific concept with a new word reflects a broader trend in scientific communication. Especially in medicine and biology, where long, technical phrases can be a barrier to understanding, naming innovations often make science more accessible and practical for professionals and the public alike.
The term penicillin helped medical researchers and pharmaceutical developers streamline discussions and publications. It also allowed for easier branding and recognition as the drug moved into clinical trials and eventually into production for use in World War II and beyond.
Legacy of a Word
Today, penicillin is not just a scientific term—it’s a symbol of one of the greatest medical breakthroughs of the 20th century. Its discovery has saved millions of lives and remains the foundation of modern antibiotic therapy. The word that Fleming coined has become part of the global medical vocabulary, taught in schools and known by the general public.
Fleming’s seemingly simple decision to replace a “cumbersome phrase” with one precise word is a testament to the power of language in science. It underscores how terminology can influence the way discoveries are communicated, remembered, and applied for generations.
