Theta

Theta (uppercase Θ or ϴ, lowercase θ (which resembles digit 0 with horizontal line) or ϑ; Ancient Greek: , thē̂ta, [tʰɛ̂ːta]; Modern: , thī́ta, [ˈθita]; UK /ˈθiːtə/, US /ˈθeɪtə/) is the eighth letter of the Greek alphabet, derived from the Phoenician letter Teth . In the system of Greek numerals it has a value of 9.

In Ancient Greek, θ represented the aspirated voiceless dental plosive /t̪ʰ/, but in Modern Greek it represents the voiceless dental fricative /θ/.

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