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theta wave

American  

noun

Physiology.

  1. any of the brain waves constituting theta rhythm.

Etymology

Origin of theta wave

First recorded in 1965–70

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.