First recorded in 1350–1400.
Comes via Middle English from the Latin word tortuōsus, which derives from the verb torquēre, “to twist, bend.”
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\r\nEXAMPLES OF TORTUOUS\r\n

The tortuous road through the mountains made for a challenging but scenic drive.
The author's writing style was known for its elegant prose and tortuous plot twists.

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natural killer cell

noun

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