fo·ment 
/ˈfoʊˌmɛnt/ verb
fo·ments; fo·ment·ed; fo·ment·ing /ˈfoʊˌmɛnt/ verb [+ obj] formal : to cause or try to cause the growth or development of (something bad or harmful) : incite
▪ foment rebellion/war/revolution ▪ He was accused of fomenting violence.
▪ foment rebellion/war/revolution ▪ He was accused of fomenting violence.
— fo·ment·er noun, plural fo·ment·ers [count]
