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theta

American  
[they-tuh, thee-] / ˈθeɪ tə, ˈθi- /

noun

  1. the eighth letter of the Greek alphabet (Θ, θ).

  2. the consonant sound represented by this letter.


theta British  
/ ˈθiːtə /

noun

  1. the eighth letter of the Greek alphabet (Θ, θ), a consonant, transliterated as th

  2. the lower-case form of this letter used in phonetic transcription to represent the voiceless dental fricative th as in thick, both Compare edh

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of theta

1595–1605; < Greek thêta < Semitic See teth

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

EEG analysis revealed that pairs of strangers exhibited greater intra-brain synchronization in the theta band, compared to acquainted pairs.

From Science Daily • Apr. 23, 2024

Sylvie Doublié, PhD, an alumnus of UNC-Chapel Hill and professor of microbiology and molecular genetics at the University of Vermont, then solved the first structure of polymerase theta.

From Science Daily • Nov. 15, 2023

Stroik had another breakthrough finding: polymerases theta and delta are physically attached to one another.

From Science Daily • Nov. 15, 2023

The five common brain-wave types, named alpha, beta, gamma, delta and theta depending on their oscillation rate, signify different states of the brain.

From Scientific American • Jun. 16, 2023

The EEG research found intensification over time of theta waves in the prefron- tal cortex, thought to be a measure of sustained attention.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel