roil

Etymology

Origin uncertain. Possibly from French or Middle French rouiller (“to rust, make muddy”), from Old French rouil (“mud, rust”), from Vulgar Latin *robicula, from Latin robigo (“rust, blight”)

verb

1. (transitive, of a fluid, especially a liquid) To render turbid by stirring up the dregs or sediment of.
   to roil wine, cider, etc, in casks or bottles
   to roil a spring
   dust storms roiling the skies
   [of St Leonards in East Sussex in 1947] A sort of roiling mist seemed year-round to hold the town in its grip. 2015, David Hare, chapter 1, in The Blue Touch Paper
2. (transitive, of a person or group of people) To annoy; to make angry; to throw into discord.
   That his friends should believe it, was what roiled him exceedingly. 1890, Roger North, Lives of the Norths
   […] and amid Musk’s sale of 10% of his Tesla stock, a process that roiled markets, cost him billions and should produce enough tax revenue to fund the Commerce Department for a year. December 13 2021, Molly Ball, Jeffrey Kluger, Alejandro de la Garza, “Elon Musk: Person of the Year 2021”, in Time
3. (intransitive) To bubble, seethe.
   By noon, Brian's stomach had begun to roil and knot. He hurried down to the bathroom at the end of the hall in his stocking feet, closed the door, and vomited into the toilet bowl as quietly as he could. 1991, Stephen King, Needful Things
   Throughout the 1500s, the populace roiled over a constellation of grievances of which the forest emerged as a key focal point. The popular late Middle Ages fictional character Robin Hood, dressed in green to symbolize the forest, dodged fines for forest offenses and stole from the rich to give to the poor. But his appeal was painfully real and embodied the struggle over wood. 2006, Edwin Black, chapter 2, in Internal Combustion
   These videos are the stone truth. Quaking proof of insult, seasick funerals. Livestreamed or uploaded, or suppressed then suspiciously unearthed as found footage. Last week, the archive grew by two, and now the nation’s roiling. 2020-06-03, Wesley Morris, “The Videos That Rocked America. The Song That Knows Our Rage.”, in New York Times
4. (obsolete, intransitive) To wander; to roam.
5. (dialect, intransitive) To romp.
   The finale was a romp in which the entire troupe burst out of the bouldering cave and roiled along the walls. 1991, Climbing - Issues 127-129, page 34
   As artists they were exploratory; in Rose Colored Dance they performed in playful embrace, smelled each other's feet, and roiled in mischief, rolling on top of each other. 2017, Sondra Fraleigh, Tamah Nakamura, Hijikata Tatsumi and Ohno Kazuo
   When the children returned from school, Pip sat among them as they did their homework. He peeled children off the floor when they roiled in frustration and plucked cats from the furniture. 2019, Vita Murrow, High-Five to the Hero, page 78
   A school let out, teens in their miraculously white, pressed shirts and blue pants and skirts, surely having come that morning from crowded, dirt-floored huts without water. They roiled over the sidewalk and flowed around me, a sweaty, old-lady tourist in her long-sleeved, 50 SPF shirt, pants, and pastel hat – a lump in their path. 2020, Richard Blanco, Caridad Moro, Nikki Moustaki, Grabbed, page 58