To roil is to agitate or make angry.
(verb)See roil in Webster's New World College Dictionary
transitive verb
Origin: Fr rouiller < OFr rouil, roille, rust, mud, ult. < L robigo, rust, akin to ruber, red
intransitive verb
See roil in American Heritage Dictionary 4
verb roiled, roil·ing, roils verb, transitive
Origin:
Origin: Origin unknown
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