Simple Definition of roil
: to upset (someone or something) very much : to cause (someone or something) to become very agitated or disturbed
: to move in a violent and confused way
Examples of roil
Financial markets have been roiled by the banking crisis.
<the waters of the gulf tossed and roiled as the hurricane surged toward the shore>
Origin of roil
First Known Use: 1590
Seen and Heard
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