Use the arrow keys to move between letters. Press Enter or Space on the first letter of a word, then again on the last letter. Press Escape to cancel.
A few of the words
- FLEMING
- Alexander Fleming was born in Ayrshire, Scotland in 1881. He was awarded the Nobel Prize in Physiology or Medicine in 1945, sharing it with Howard Florey and Ernst Boris Chain, who later purified penicillin for clinical use.Find this word in the grid to read its note.
- LONDON
- Fleming made his discovery at St. Mary's Hospital in Paddington, London, a lab he had worked in since 1906. The room where the famous petri dish sat is now part of the Alexander Fleming Laboratory Museum.Find this word in the grid to read its note.
- SPORE
- The mold that drifted onto Fleming's dish was almost certainly carried as an airborne spore from a mycology lab one floor below, making the whole discovery a remarkable accident of open windows and curious science.Find this word in the grid to read its note.
- ANTIBIOTIC
- Fleming's original paper, published in 1929, described a substance he called 'penicillin', a name that would become one of the most recognized words in the history of medicine.Find this word in the grid to read its note.
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penicillin discovery word search
Penicillin: The Discovery That Changed Medicine: a free online word search
Penicillin discovery word search, playable online right now, marking the September 28, 1928 morning Fleming found mold where he'd left none.
About Penicillin: The Discovery That Changed Medicine
On September 28, 1928, Alexander Fleming returned to his laboratory at St. Mary's Hospital in London after a summer holiday and noticed something remarkable: a patch of Penicillium notatum mold had landed on an uncovered petri dish and was dissolving the bacteria around it. That quiet observation, made on a single contaminated dish, set in motion decades of research that would eventually give the world its first true antibiotic. By the time penicillin entered widespread use in the 1940s, it had already begun saving lives on a scale that medicine had never seen before.
How to play
- 1Find a word.Tap its first letter, then tap along to its last. The trail fills in and finishes itself when it spells a word. Or press the first letter and drag.
- 2Words run in straight lines.Across and down, and on the harder difficulties diagonally and backwards.
- 3It marks itself.Each word you find takes on its own soft color on the grid and is crossed off the list.
- 4Choose a difficulty.Relaxed, Classic or Challenging set those directions and how much the word list helps, never the grid size. Tap the A buttons at the top to enlarge the letters, or pinch the grid.

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