When used as a diacritic mark, the term dot refers to the glyphs "combining dot above" (◌̇), and "combining dot below" (◌̣)
which may be combined with some letters of the extended Latin alphabets in use in
a variety of languages. Similar marks are used with other scripts.
Overdot
Language scripts or transcription schemes that use the dot above a letter as a diacritical mark:
The Latin orthography for Chechen includes ċ, ç̇, ġ, q̇, and ẋ.
Traditional Irish typography, where the dot denotes lenition, and is called a ponc séimhithe or buailte "dot of lenition": ḃ ċ ḋ ḟ ġ ṁ ṗ ṡ ṫ. Alternatively, lenition may be represented by a following letter h, thus: bh ch dh fh gh mh ph sh th. In Old Irish orthography, the dot was used only for ḟ ṡ, while the following h was used for ch ph th; lenition of other letters was not indicated. Later the two systems spread to the entire set of lenitable consonants and competed with each other. Eventually the standard practice was to use the dot when writing in Gaelic script and the following h when writing in antiqua. Thus ċ and ch represent the same phonetic element in Modern Irish.
Lithuanian: ė is pronounced as [eː], as opposed to ę, which is pronounced a lower [æː] (formerly nasalised), or e, pronounced [ɛ,æː].
In the Canadian Aboriginal Syllabics orthography for the Cree, Ojibwe, and Inuktitut languages, a dot above a symbol signifies that the symbol's vowel should be a long vowel—the equivalent effect using the Roman orthography is achieved by doubling the vowel (ᒥ = mi, ᒦ = mii), placing a macron over the vowel (ᑲ = ka, ᑳ = kā), or placing a circumflex over the vowel (ᓄ = no, ᓅ = nô).
In Turkish, the dot above lowercase i and j (and uppercase İ) is not regarded as an independent diacritic but as an integral part of the letter. It is called a tittle. I without an overdot is a separate letter.
In the Rheinische Dokumenta phonetic writing system overdots denote a special pronunciation of r.
In a number of languages, an underdot indicates a raised or relatively high vowel, often the counterpart of a lower vowel marked with an ogonek or left unmarked.
In Romagnol, ẹ ọ are used to represent [e, o], e.g. part of Riminese dialect fradẹll, ọcc[fraˈdell,ˈotʃː] "brothers, eyes".
In academic notation of Old Latin, ẹ̄ (e with underdot and macron) represents the long vowel, probably /eː/, that developed from the early Old Latin diphthong ei. This vowel usually became ī in Classical Latin.
In academic transcription of Vulgar Latin, used in describing the development of the Romance languages, ẹ and ọ represent the close-mid vowels /e/ and /o/, in contrast with the open-mid vowels /ɛ/ and /ɔ/, which are represented as e and o with ogonek (ę ǫ).
Academic transcription of Middle English uses the same conventions as Vulgar Latin above.
In academic transcription of Serbo-Croatian dialects, ẹ ọ ạ (typically /e//o//ɐ/) represent higher vowels than standard e o a, and the first two often contrast with lower vowels marked with a comma below, e̦ o̦ (typically /ɛ//ɔ/).
In Inari Sami, an underdot denotes a half-long voiced consonant: đ̣, j̣, ḷ, ṃ, ṇ, ṇj, ŋ̣, ṛ, and ṿ. The underdot is used in dictionaries, textbooks, and linguistic publications only.
In the DIN 31636 and ALA-LCRomanization of Hebrew, ṿ represents vav (ו), while v without the underdot represents beth (ב). ḳ represents qoph (ק) while k represents kaph (כ). ḥ represents chet (ח).
The underdot is also used in the PDA orthography for Domari to show pharyngealization—the underdotted consonants ⟨ḍ ḥ ṣ ṭ ẓ⟩ represent the emphaticized sounds /d̪ˤħsˤt̪ˤzˤ/.
Vietnamese: The nặngtone (low, glottal) is represented with a dot below the base vowel: ạ ặ ậ ẹ ệ ị ọ ộ ợ ụ ự ỵ.
In Igbo, an underdot can be used on i, o, and u to make ị, ọ, and ụ. The underdot symbolizes a reduction in the vowel height.
In Yoruba, an underdot can be used on e and o to make ẹ and ọ, symbolizing a reduction in the vowel height, as well as on s to make ṣ, symbolizing a postalveolar articulation.
Underdots are used in the Rheinische Dokumenta phonetic writing system to denote a voiced s and special pronunciations of r and a.
In the Fiero-Rhodes orthography for Eastern Ojibwe and Odaawaa, in g̣, ḥ, and ḳ, underdot is used to indicate labialization when either ⟨o⟩ or ⟨w⟩ following them was lost in syncope.
In Canadian Aboriginal Syllabics, in addition to the middle dot as a letter, centred dot diacritic, and dot above diacritic, there also is a two-dot diacritic in the Naskapi language representing /_w_V/ which depending on the placement on the specific Syllabic letter may resemble a colon when placed vertically, diaeresis when placed horizontally, or a combination of middle dot and dot above diacritic when placed either at an angle or enveloping a small raised letter ᓴ. Additionally, in Northwestern Ojibwe, a small raised /wi/ as /w/, the middle dot is raised farther up as either ᣜ or ᣝ; there also is a raised dot "Final" (ᣟ), which represents /w/ in some Swampy Cree and /y/ in some Northwestern Ojibwe.
