lac·​to·​ba·​cil·​lus ˌlak-tō-bə-ˈsi-ləs How to pronounce lactobacillus (audio)
: any of a genus (Lactobacillus) of bacteria that produce lactic acid

Examples of lactobacillus in a Sentence

Recent Examples on the Web According to Solawave, the prebiotic beta-glucan and the mushroom extract sparassis crispa extract help with the skin’s moisture, while the probiotic lactobacillus ferment lysate betters the appearance of the skin. Alyssa Grabinski, Peoplemag, 13 June 2023 It's known that one kind of probiotic, lactobacillus acidophilus, can stimulate bacterial growth in the gut and cause weight increase. Amber Smith, Discover Magazine, 20 Oct. 2022 This mixed culture ale was fermented with a blend of brettanomyces and lactobacillus to create a sour stage for showcasing Oregon native Silvan blackberries from West Union Gardens, plus a generous heap of lime zest. oregonlive, 31 Mar. 2023 This mildly sour, chewy bread is made with a lactic acid starter containing lactobacillus strains, a friendly type of bacteria that adds good microbes to the bakery staple. Jessica Migala, Health, 6 Feb. 2023 The other superstar of Blu Atlas’s cleanser formula is lactobacillus fermented filtrate. The Salt Lake Tribune, 9 May 2022 Other ingredients include lactobacillus ferment and pomegranate seed oil, which intensely soothe and nourish the skin. Blu Atlas, The Salt Lake Tribune, 30 Sep. 2022 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'lactobacillus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin

First Known Use

1924, in the meaning defined above

Time Traveler
The first known use of lactobacillus was in 1924

Dictionary Entries Near lactobacillus

Cite this Entry

“Lactobacillus.” Dictionary, Merriam-Webster, Accessed 25 Sep. 2023.

Medical Definition


lac·​to·​ba·​cil·​lus ˌlak-tō-bə-ˈsil-əs How to pronounce lactobacillus (audio)
capitalized : a genus of gram-positive nonmotile lactic-acid-forming bacteria of the family Lactobacillaceae including various commercially important lactic acid bacteria
plural lactobacilli
-ˌī also -ˌē
: any bacterium of the genus Lactobacillus

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