To roil means to stir up or churn. A stormy ocean might roil, or even a restless crowd.

The word roil is often confused with rile, which has a slightly different meaning. If you roil someone you're stirring them up but not necessarily annoying them. To rile someone is to deliberately provoke or antagonize them. Usually there's no roiling without riling. Muhammad Ali roiled much of America when he refused to be drafted for the Vietnam War.

Definitions of roil
  1. verb
    make turbid by stirring up the sediments of
    synonyms: rile
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    muddle, puddle
    make into a puddle
    type of:
    agitate, commove, disturb, raise up, shake up, stir up, vex
    change the arrangement or position of
  2. verb
    be agitated
    synonyms: boil, churn, moil
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    roll, seethe
    boil vigorously
    type of:
    move so as to change position, perform a nontranslational motion
Word Family

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