From Middle English ferment, from Middle French ferment, from Latin fermentō, from fermentum ("substance causing fermentation"), from fervēre.

• • (RP) IPA: /fəˈmɛnt/
  • (America) IPA: /fɚˈmɛnt/
  • (RP) IPA: /ˈfɜː.mɛnt/
  • (America) IPA: /ˈfɚ.mɛnt/

ferment (ferments, present participle fermenting; simple past and past participle fermented)

1. To react, using fermentation; especially to produce alcohol by aging or by allowing yeast to act on sugars; to brew.
2. To stir up, agitate, cause unrest or excitement in.
   • 1713, Alexander Pope, “Windsor-Forest. […]”, in The Works of Mr. Alexander Pope, volume I, London: […] W[illiam] Bowyer, for Bernard Lintot, […], published 1717, →OCLC ↗:

     Ye vigorous swains! while youth ferments your blood.

   • a. 1749 (date written), James Thomson, “Winter”, in The Seasons, London: […] A[ndrew] Millar, and sold by Thomas Cadell, […], published 1768, →OCLC ↗, page 165 ↗, lines 10–14:

     Pleas'd have I wander'd thro' your rough domain; / Trod the pure virgin-ſnows, myſelf as pure; / Heard the winds roar, and the big torrent burſt; / Or ſeen the deep fermenting tempeſt brew'd, / In the grim evening ſky.

• French: fermenter
• German: gären
• Italian: fermentare
• Portuguese: fermentar
• Russian: броди́ть
• Spanish: fermentar

• German: stören, anstacheln
• Italian: fermentare
• Russian: волнова́ть

ferment (plural ferments)

1. Something, such as a yeast or barm, that causes fermentation.
2. A state of agitation or of turbulent change.
   • a. 1729, John Rogers, The Difficulties of Obtaining Salvation:

     Subdue and cool the ferment of desire.

   • 14 November, 1770, Junius, letter to the Right Honourable Lord Mansfield

     The nation is in a ferment.

   • 1919, Ronald Firbank, Valmouth, Duckworth, hardback edition, page 104

     Clad in a Persian-Renaissance gown and a widow's tiara of white batiste, Mrs Thoroughfare, in all the ferment of a Marriage-Christening, left her chamber on vapoury autumn day and descending a few stairs, and climbing a few others, knocked a trifle brusquely at her son's wife's door.

3. A gentle internal motion of the constituent parts of a fluid; fermentation.
   • 1748, James Thomson, “Canto II”, in The Castle of Indolence: […], London: […] A[ndrew] Millar, […], →OCLC ↗, stanza XXX, page 56 ↗:

     A Rage of Pleaſure madden'd every Breaſt, / Down to the loweſt Lees the Ferment ran: [...]

4. A catalyst.

• German: Gärmittel
• Portuguese: fermento
• Russian: ферме́нт

• Russian: возбужде́ние