The eighth letter of the Modern Greek alphabet, ninth in Old Greek: Θ, θ.
The measure of an angle.
The sensitivity of the value of a derivative with respect to time; the "time decay".
Designating a level of brain activity as measured by electroencephalography having a frequency of between four and seven cycles per second (associated with drowsiness in adults).
The voiceless dental fricative represented by θ.
All clues having "THETA"
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