Who coined the term 'microbe'?

Charles-Emmanuel Sédillot coined the term “microbe” in 1878. The French military physician and surgeon introduced the word while discussing the growing number of names for microscopic organisms associated with the discoveries of Louis Pasteur and other researchers.

The term combines the Greek roots mikros, meaning “small,” and bios, meaning “life.” Sédillot favored it because it was shorter and more general than the many technical labels then being used for microscopic living forms. His proposal appeared in a paper on Pasteur’s influence on surgical progress.

Sédillot was not the first person to observe microorganisms. Antonie van Leeuwenhoek had described microscopic “animalcules” in the 17th century, and Pasteur and Robert Koch later helped establish how particular microbes cause fermentation and disease. Those figures are therefore commonly, but incorrectly, chosen as the word’s originator.

Émile Littré helped popularize and formalize the term by including it in a later edition of his medical dictionary in 1886. Today, “microbe” is an informal umbrella term rather than a precise taxonomic rank, covering organisms such as bacteria, fungi, and some protozoa.