The"ta (?), n. [L., fr. Gr. qh^ta, the Greek letter θ,
A letter of the Greek alphabet corresponding to th in English; -- sometimes called the unlucky letter, from being used by the judges on their ballots in passing condemnation on a prisoner, it being the first letter of the Greek qa`natos, death.
Theta function Math., one of a group of functions used in developing the properties of elliptic functions.
© Webster 1913.