Eta ( EE-tə, AY-tə; uppercase Η, lowercase η; ē̂ta or ita) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel, . Originally denoting the voiceless glottal fricative,, in most dialects of Ancient Greek, its sound value in the classical Attic dialect was a long open-mid front unrounded vowel,, which was raised to in Hellenistic Greek, a process known as iotacis... Wikipedia