The P.3 strain of the SARS-CoV-2 virus that causes COVID-19.

The eighth letter of the Modern Greek alphabet, ninth in Old Greek: Θ, θ. / (mathematics) The measure of an angle.

(Greek mythology) One of the Nereids; the mother of Achilles / (astronomy) 17 Thetis, one of the main belt asteroids.

(Scientology) A soul, spirit or being.

A type of electrical activity in the brain; a brain wave with a frequency of 4-8 hertz.

A type of electrical activity in the brain: brain waves with a frequency of 4-8 hertz.

(mathematics) Any of a group of special functions of several complex variables, important in many areas, including the theories of abelian varieties and moduli spaces, and of quadratic forms.

plural of theta function

(prosody) of or pertaining to a thesis / dogmatic

plural of theta wave