Close front unrounded vowel in the context of "Germanic umlaut"

Eta (/ˈiːtə, ˈeɪtə/ EE-tə, AY-tə; uppercase Η, lowercase η; Ancient Greek: ἦτα ē̂ta [ɛ̂ːta] or Greek: ήτα ita [ˈita]) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel, [i]. Originally denoting the voiceless glottal fricative, [h], in most dialects of Ancient Greek, its sound value in the classical Attic dialect was a long open-mid front unrounded vowel, [ɛː], which was raised to [i] in Hellenistic Greek, a process known as iotacism or itacism.

In the ancient Attic number system (Herodianic or acrophonic numbers), the number 100 was represented by "Η", because it was the initial of ΗΕΚΑΤΟΝ, the ancient spelling of ἑκατόν = "one hundred". In the later system of (Classical) Greek numerals eta represents 8.

İ, or i, called dotted I or i-dot, is a letter used in the Latin-script alphabets of Azerbaijani, Crimean Tatar, Gagauz, Kazakh, Tatar, and Turkish. It commonly represents the close front unrounded vowel /i/ except in Kazakh in which it additionally represents the voiced palatal approximant /j/ and the diphthongs /ɪj/ and /əj/. All languages that use it also use its dotless counterpart I, but not the basic Latin letter I.

I with diaeresis (Ӥ ӥ; italics: Ӥ ӥ) is a letter of the Cyrillic script. It is used in the Udmurt language, where it represents the close front unrounded vowel /i/, and is used only after the non-palatalized dentals /d/, /z/, /l/, /n/, /s/ and /t/; the Cyrillic letter I (Ии) is used otherwise.

Yodh (also spelled jodh, yod, or jod) is the tenth letter of the Semitic abjads, including Phoenician yōd 𐤉, Hebrew yod י‎, Aramaic yod 𐡉, Syriac yōḏ ܝ, and Arabic yāʾ ي‎. It is also related to the Ancient North Arabian 𐪚‎‎‎, South Arabian 𐩺, and Ge'ez የ. Its sound value is /j/ in all languages for which it is used; in many languages, it also serves as a long vowel, representing /iː/.

The Phoenician letter gave rise to the Greek Iota (Ι), Latin I and J, Cyrillic І, Coptic Iauda (Ⲓ) and Gothic eis .

Iotacism (Ancient Greek: ἰωτακισμός, iotakismos) or itacism is the process of vowel shift by which a number of vowels and diphthongs converged towards the pronunciation [i] in post-classical Greek and Modern Greek. The term "iotacism" refers to the letter iota, the original sign for [i], with which these vowels came to merge. The alternative term itacism refers to the new pronunciation of the name of the letter eta as [ˈita] after the change.

Iota (/aɪˈoʊtə/ ; /ˈjota/, uppercase Ι, lowercase ι; Greek: ιώτα) is the ninth letter of the Greek alphabet. It was derived from the Phoenician letter Yodh. Letters that arose from this letter include the Latin I and J, the Cyrillic І (І, і), Yi (Ї, ї), and Je (Ј, ј), and iotated letters (e.g. Yu (Ю, ю)). In the system of Greek numerals, iota has a value of 10.

Iota represents the close front unrounded vowel IPA: [i]. In early forms of ancient Greek, it occurred in both long [iː] and short [i] versions, but this distinction was lost in Koine Greek. Iota participated as the second element in falling diphthongs, with both long and short vowels as the first element. Where the first element was long, the iota was lost in pronunciation at an early date, and was written in polytonic orthography as iota subscript, in other words as a very small ι under the main vowel. Examples include ᾼ ᾳ ῌ ῃ ῼ ῳ. The former diphthongs became digraphs for simple vowels in Koine Greek.