the·ta / ˈ[unvoicedth]ātə; ˈ[unvoicedth]ē-/ • n. the eighth letter of the Greek alphabet (Θ, θ), transliterated as ‘th.’ ∎  (Theta) [followed by Latin genitive] Astron. the eighth star in a constellation: Theta Draconis. ∎  [as adj.] Chem. denoting a temperature at which a polymer solution behaves ideally as regards its osmotic pressure. ∎  [as adj.] denoting electrical activity observed in the brain under certain conditions, consisting of oscillations having a frequency of 4 to 7 hertz: theta rhythm.• symb. ∎  (θ) temperature (esp. in degrees Celsius). ∎  (θ) a plane angle. ∎  (θ) a polar coordinate. Often coupled with φ.

Theta (Journal)

Scholarly journal of parapsychology published quarterly by the Psychical Research Foundation. Its title derives from the initial letter of the Greek word, Thanatos (death) and its concern is mainly with research on the problem of survival of bodily death. It was edited for many years by William G. Roll. Theta has been published since 1963. The publication can be reached c/o Dr. Andrew Nichols, P.O. Box 142193, Gainesville, FL 32614-2193.

theta the eighth letter of the Greek alphabet (Θ, θ), transliterated as ‘th’. In ancient Greece, on the ballots used in voting upon a sentence of life or death, this character stood for thanatos ‘death’, which gave rise to allusive uses.