Ferment or foment?
ferment is a verb meaning “To react, using fermentation; especially to produce alcohol by aging or by…”; foment is a verb meaning “To incite or cause troublesome acts; to encourage; to instigate”. In written English (wordfreq, 2021 data) ferment is about 2.8 times as common as foment.
What is the difference between ferment and foment?
| ferment | foment | |
|---|---|---|
| Part of speech | verb, noun | verb, noun |
| Meaning | To react, using fermentation; especially to produce alcohol by aging or by allowing yeast to act on sugars; to brew To stir up, agitate, cause unrest or excitement in Something, such as a yeast or barm, that causes fermentation | To incite or cause troublesome acts; to encourage; to instigate To apply a poultice to; to bathe with a cloth or sponge Fomentation |
| Example | 14 November, 1770, Junius, letter to the Right Honourable Lord Mansfield The nation is in a ferment | He was arrested for fomenting a riot; after all, it's bad enough being in a riot but starting one is much worse |
| Forms | ferments, fermenting, fermented | foments, fomenting, fomented |
| Pronunciation | /fəˈmɛnt/ /fɚˈmɛnt/ /ˈfɜː.mɛnt/ | /fəʊˈmɛnt/ /foʊˈmɛnt/ /fəˈmɛnt/ |
| In writing | about once in every 1 million words | about once in every 4 million words |
Sources: ferment and foment in the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Every current meaning of ferment and foment
ferment
- 1
To react, using fermentation; especially to produce alcohol by aging or by allowing yeast to act on sugars; to brew
- 2
Something, such as a yeast or barm, that causes fermentation
- 3
To stir up, agitate, cause unrest or excitement in
- 4
A state of agitation or of turbulent change
14 November, 1770, Junius, letter to the Right Honourable Lord Mansfield The nation is in a ferment
- 5
A gentle internal motion of the constituent parts of a fluid; fermentation
- 6
A catalyst
foment
- 1
To incite or cause troublesome acts; to encourage; to instigate
He was arrested for fomenting a riot; after all, it's bad enough being in a riot but starting one is much worse
- 2
Fomentation
- 3
To apply a poultice to; to bathe with a cloth or sponge
Source: the English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0); obsolete, archaic, dialect and rare senses left out.
Which is more common, ferment or foment?
ferment appears about once in every 1 million words; foment about once in every 4 million words.
ferment about once in every 1 million wordsfoment about once in every 4 million words
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How many people search ferment vs foment?
“ferment vs foment” is searched about 70 times a month on Google and 10 on Bing in the United States. Google counts close variants of a query together (“foment vs ferment”, “ferment or foment”).
Sources: Google Ads keyword data through DataForSEO and Microsoft Advertising keyword data through DataForSEO, the average month from September 2025 to August 2026.