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octan

American  
[ok-tuhn] / ˈɒk tən /

adjective

  1. (of a fever) occurring every eighth day.

noun

  1. an octan fever.

Etymology

Origin of octan

1895–1900; < French octane, Middle French octaine, derivative of Latin octō eight, on the model of quartaine quartan

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.