microbe

noun

mi·​crobe ˈmī-ˌkrōb 

: microorganism, germ

microbial

mī-ˈkrō-bē-əl 

adjective

or less commonly microbic

mī-ˈkrō-bik 

microbially

mī-ˈkrō-bē-ə-lē 

adverb

Did you know?

A hint of the Greek word bios, meaning "life", can be seen in microbe. Microbes, or microorganisms, include bacteria, protozoa, fungi, algae, amoebas, and slime molds. Many people think of microbes as simply the causes of disease, but every human is actually the host to billions of microbes, and most of them are essential to our life. Much research is now going into possible microbial sources of future energy; algae looks particularly promising, as do certain newly discovered or created microbes that can produce cellulose, to be turned into ethanol and other biofuels.

Examples of microbe in a Sentence

Recent Examples on the Web

Earlier this month, a team that included researchers from Nvidia and Microsoft trained an AI model on genetic data from more than a million species, most of them microbes that had never been publicly cataloged before. —Reed Albergotti, semafor.com, 23 Jan. 2026

But another is finding new drugs against resistant microbes. —Alex Knapp, Forbes.com, 22 Jan. 2026

As for the gut microbes, the team observed similar subtle shifts. —Laura Baisas, Popular Science, 21 Jan. 2026

These additions may reduce the cows’ methane production by changing how the microbes in their stomachs process carbohydrates. —Sara Place, The Conversation, 16 Jan. 2026

Word History

Etymology

International Scientific Vocabulary micr- + Greek bios life — more at quick entry 1

First Known Use

1878, in the meaning defined above

Rhymes for microbe

• bathrobe
• earlobe
• niobe
• wardrobe
• globe
• jobe
• lobe
• probe
• robe
• strobe
• microprobe

Kids Definition

microbe

noun

mi·​crobe ˈmī-ˌkrōb 

: microorganism, germ

microbial

mī-ˈkrō-bē-əl 

adjective

also microbic

-bik 

Medical Definition

microbe

noun

mi·​crobe ˈmī-ˌkrōb 

: microorganism, germ

—used especially of pathogenic bacteria