Word.ws English Dictionary

bacilli

/bəˈsɪl.aɪ/

bacilli is the plural of bacillus.

Meaning of bacillus

Noun

bacillus (plural bacilli)

  1. Any of various rod-shaped, spore-forming aerobic bacteria in the genus Bacillus, some of which cause disease.
    • 'This again,' said the Bacteriologist, slipping a glass slide under the microscope, 'is a preparation of the celebrated Bacillus of cholera - the cholera germ.'1895, H. G. Wells, The Stolen Bacillus
  2. Any bacilliform (rod-shaped) bacterium.
  3. (broadly, figuratively) Something which spreads like bacterial infection.
    • The “bacillus of boom or depression,” he wrote, travels freely “from country to country.”1934 [2018], Gottfried Haberler quoted in Quinn Slobodian, Globalists, 71

Words formed from bacilli

Phrases with bacilli

Questions about bacilli

What is bacilli the plural of?
Bacilli is the plural of bacillus.
How do you pronounce bacilli?
Bacilli is pronounced /bəˈsɪl.aɪ/ (US).

Words near bacilli in the dictionary

  1. bacillariophyceans
  2. bacillariophyte
  3. bacillariophytes
  4. bacillary
  5. bacillemia
  6. bacilli
  7. bacillian
  8. bacilliary
  9. bacillibactin
  10. bacillicidal
  11. bacillicide

Source and license

Adapted from Wiktionary: bacilli (page history and authors); bacillus (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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