Origin: 1350–1400; ME fomenten < LL fōmentāre, v. deriv. of L fōmentum soothing application, poultice, contr. of *fōvimentum, equiv. to fōv(ēre) to keep warm + -i- -i-+ -mentum-ment
[Middle English fomenten, to apply warm liquids to the skin, from Old French fomenter, from Late Latin fōmentāre, from Latin fōmentum, poultice, from fovēre, to warm; see dhegwh- in Indo-European roots.] fo·ment'er n.
c.1400 (implied in fomentation), from M.Fr. fomenter, from L.L. fomentare, from L. fomentum "warm application, poultice," from fovere "to warm, cherish, encourage." Extended sense of "stimulate, instigate" (1622) was in the Fr.