To nurse to life or activity; to cherish and promote by excitements; to encourage; to abet; to instigate; used often in a bad sense; as, to foment ill humors
If someone or something foments trouble or violent opposition, they cause it to develop. They accused strike leaders of fomenting violence. = incite. foment revolution/trouble/discord etc to cause trouble and make people start fighting each other or opposing the government = stir up (fomentare, from fovere )
[ 'fO-"ment, fO-' ] (transitive verb.) circa 1613. Middle English fomenten to apply a warm substance to, from Late Latin fomentare, from Latin fomentum compress, from fovEre to heat, soothe; akin to Lithuanian degti to burn, Sanskrit dahati it burns.