1.To render turbid by stirring up the dregs or sediment of; as, to roil wine, cider, etc., in casks or bottles; to roil a spring.
2.To disturb, as the temper; to ruffle the temper of; to rouse the passion of resentment in; to perplex. "That his friends should believe it, was what roiled him (Judge Jeffreys) exceedingly." Note: Provincial in England and colloquial in the United States. A commoner, but less approved, form is rile.