Definition of roil in English:



  • 1literary with object Make (a liquid) turbid or muddy by disturbing the sediment.

    ‘winds roil these waters’
    murky, cloudy, muddied, turbid, opaque, impure
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    1. 1.1no object (of a liquid) move in a turbulent, swirling manner.
      ‘the sea roiled below her’
      • ‘On volcanically active planets like Venus, the surface roils and churns so quickly that solid crust does not have a chance to form.’
      • ‘The clouds are pink, the seas around Hook's ship surge and roil, and the fairies dance deep in the forest.’
      • ‘While again Rawsthorne doesn't go so far as to lose his head or wear his heart on his sleeve, one gets the impression of great passions roiling under a relatively calm surface.’
      • ‘Beneath the veneer of landscapes, portraits and genre scenes, political rivalries roiled, and medals granted to entrants were contested hotly as matters of national pride.’
      • ‘Something of Turner's seascapes, where everything appears to be roiling, comes through.’
      • ‘The water roils around the combatants, and the sky is filled with clouds and tiny lines that intensify the sense of cataclysm.’
      • ‘The North Sea roils just off the former hippie village of Monster, 40 miles southwest of Amsterdam.’
      • ‘Below him water burbles, roils, and freezes into 300-pound blocks.’
      • ‘Back on the ship, as the plot thickens and roils, our brave buccaneers flounder in the doldrums.’
      • ‘In the great Chaplin-versus-Keaton debate that's been roiling for decades among cinephiles, I come down firmly on the Chaplin side.’
      • ‘The core mantle boundary is a complex and dynamic area that churns and chugs as the liquid iron core roils at the bottom of the rock-like mantle.’
      • ‘The waves roil mightily, and batter and strike the ship so that they crush both sides of the hull and the planking almost shatters.’
      bubble, fizz, foam, cream, lather
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  • 2

    US term for rile (sense 1)
    • ‘Any religious film with violence is bound to roil some people.’
    • ‘He appears to have roiled some executives who were turned off by his hard-charging approach and overselling the merger's synergies.’
    • ‘That roiled his colleagues and, some argued, prolonged a stoppage that wiped out the World Series.’
    • ‘That comment still roils the ultra-liberal faculty at the university.’


Late 16th century: perhaps from Old French ruiler ‘mix mortar’, from late Latin regulare ‘regulate’.