X with Accent: ẋ ẍ Count Derivatives, Chechen ẋ, Kurdish ẍ
An x with accent exists as one character only as ẋ or ẍ, and its marks usually mean calculus, not sound. Unicode's names list calls the dot above a derivative and the diaeresis a double derivative. As letters, ẋ wrote the Chechen [ħ] in the Roman alphabet of 1992, and ẍ writes the Kurdish [ɣ] and the Mam /ʃ/.
How do you type ẋ on a keyboard or phone?
On a Mac, ẋ is Fn/Globe+E, then search "latin small letter x with dot above", then ẋ; on Windows it is Win+., then Symbols, then ẋ. Each row below gives the documented method for one device or app; the vendor help pages they come from are linked under the table.
| Device or app | Keys |
|---|---|
| Mac | Fn/Globe+E, then search "latin small letter x with dot above", then ẋ How to type accents on a Mac |
| Windows | Win+., then Symbols, then ẋ How to type accents on Windows |
| Microsoft Word | 1e8b, then Alt+X How to type accents in Word |
| Google Docs | Insert, then Symbols, then Special characters, then search "latin small letter x with dot above" How to type accents in Google Docs |
Sources:Mac (Apple) (opens in a new tab)Windows (Microsoft) (opens in a new tab)Microsoft Word (Microsoft) (opens in a new tab)Google Docs (Google) (opens in a new tab)
- ẋ x with dot above
- Ẋ capital x with dot above
- ẍ x with diaeresis
- Ẍ capital x with diaeresis
What is the Unicode code for ẋ?
ẋ is U+1E8B, LATIN SMALL LETTER X WITH DOT ABOVE, added in Unicode 1.1 in 1993. In UTF-8 it is stored as the bytes E1 BA 8B, and the table gives every escape a developer needs.
| Code point | U+1E8B |
|---|---|
| Name | LATIN SMALL LETTER X WITH DOT ABOVE |
| Added in | Unicode 1.1 (1993) |
| UTF-8 bytes | E1 BA 8B |
| HTML | ẋ ẋ |
| CSS | \1E8B |
| JavaScript | \u1E8B |
| Python | \u1e8b |
| URL | %E1%BA%8B |
If a page shows ẋ instead of ẋ, its UTF-8 bytes are being read as Windows-1252. Serve the page as UTF-8 (<meta charset="utf-8">) to fix it.
What do the dots over ẋ and ẍ mean in physics and calculus?
In a physics book, an x with a dot is not a letter at all. Unicode's names list (opens in a new tab) gives the combining dot above, U+0307, the alias "derivative (Newtonian notation)". It calls the combining diaeresis, U+0308, a "double derivative". Wiktionary agrees: its entry for ẋ (opens in a new tab) is the differential of x in Newton's notation, the x part of a velocity, and ẍ (opens in a new tab) is the second-order differential, the x part of an acceleration.
So an x with accent in a physics book, the x with dot above or the x with diaeresis (the x with two dots), is notation first. The same names list goes on past two dots, and that is where the encoded letters stop.
| Written | Built from | Names list alias | Reads as | LaTeX | One character? |
|---|---|---|---|---|---|
| ẋ | x + U+0307 | derivative (Newtonian notation) | first derivative; velocity when x is a position | \dot{x} | yes, U+1E8B |
| ẍ | x + U+0308 | double derivative | second derivative; acceleration | \ddot{x} | yes, U+1E8D |
| x⃛ | x + U+20DB | third derivative | third derivative | \dddot{x}, with amsmath | no |
| x⃜ | x + U+20DC | fourth derivative | fourth derivative | \ddddot{x}, with amsmath | no |
We checked the last column in Node.js v26.0.0 (ICU 78.3) on 2026-10-10. Under NFC, x plus U+0307 became ẋ and x plus U+0308 became ẍ. x plus U+20DB stayed two code points. A third dot always rides on a plain x.
LaTeX has \dot and \ddot built in. The amsmath user guide (opens in a new tab) adds \dddot and \ddddot. Unicode Technical Note #28 (opens in a new tab), which defines UnicodeMath, a linear math format that Microsoft 365 apps such as Word can build up into equations, maps the same four names to U+0307, U+0308, U+20DB and U+20DC.
That note also tells math editors to turn letters used as variables into math alphabet characters from Unicode's Mathematical Alphanumeric Symbols block. For an x, the usual one is the italic 𝑥, U+1D465, not the plain x. This matters when you search. In the same test, NFC kept 𝑥 plus U+0307 as two code points, and a search for ẋ missed it. NFKC folded the pair into U+1E8B, and the search found it.
Which alphabets have written ẋ or ẍ as a letter?
A handful of alphabets use an x with accent as a letter, and none of them is in the Unicode CLDR alphabet data that AccentPad's language cards read, so this page shows no languages card. The rows below come from Wiktionary's entries for ẋ, ẍ and x (opens in a new tab), and from the place-name tables of the Institute of the Estonian Language for Chechen (opens in a new tab) and Kurdish (opens in a new tab).
| Letter | Language | Period in the source | Sound | Other spellings of that sound |
|---|---|---|---|---|
| ẋ Ẋ | Chechen | Roman alphabet of 1992 | [ħ] | Cyrillic хь; x́ or x̌ in the Roman alphabet of 1925 to 1937 |
| ẍ Ẍ | Northern Kurdish | Hawar alphabet, an optional letter | [ɣ] | x̣; x or g in the normal Hawar; Cyrillic г’ |
| ẍ Ẍ | Mam | none given | /ʃ/ | xh |
| ẍ | Asturian | late 19th to 20th century | /ʃ/ | xs in 1788; xh or x̄ in 1842; x today |
Mam, a Mayan language, sets ẍ against plain x. Wiktionary gives Mam x as /ʂ/, with the tongue curled back, and ẍ as /ʃ/, the sh of English ship.
Asturian shows why a mark ever went on the x. Wiktionary's Asturian entry says x once stood for /ks/, so /ʃ/ needed a spelling of its own. González de Posada wrote xs in 1788. Junquera Huergo wrote xh or x̄ in 1842. From the late 19th century, authors wrote ẍ. Modern Asturian x always says /ʃ/, so the mark has nothing left to do, and Wiktionary notes that new editions of old texts seldom keep it.
Do the Chechen ẋ and the Kurdish ẍ stand for the same Arabic letter?
No. Chechen was written in Arabic script until 1925, and the Kurdish Hawar table pairs each Latin letter with a letter of the Kurdish Arabic alphabet. Both Latin alphabets keep the Arabic throat letters apart, but the marks landed on different letters. The Estonian tables give the Arabic letter behind each one.
| Arabic letter | Chechen Latin | Chechen sound | Kurdish Hawar | Kurdish sound |
|---|---|---|---|---|
| ح | ẋ | [ħ] | ḧ | [ħ] |
| خ | x | [χ] | x | [x] |
| غ | ġ | [ʁ] | ẍ | [ɣ] |
Read the table across. The Chechen ẋ answers ح, a sound made low in the throat. The Kurdish ẍ answers غ, a voiced x. Kurdish writes ح as ḧ, which the h with accent page covers. So the dot of ẋ and the two dots of ẍ share no meaning. Each alphabet put a mark on whichever letter it needed.
The Kurdish ẍ is also the easier one to drop. The Hawar notes say the normal version of the alphabet writes x or g for it. Wiktionary's list of Kurdish letters puts ẍ in brackets, and its entry says the letter keeps غ apart from خ in loanwords from Arabic.
How did Chechen spell its throat sounds with x, ẋ and h?
Cyrillic Chechen writes three throat sounds with х alone or with a second sign. The Roman alphabet of 1992 gave each one a single letter, and most letters that replace a Cyrillic pair carry a dot. The Estonian table lists the letters and their sounds.
| Cyrillic | Roman, 1992 | Sound | What the dot answers |
|---|---|---|---|
| х | x | [χ] | no dot: a single Cyrillic letter |
| хь | ẋ | [ħ] | the soft sign ь |
| хӀ | h | [h] | no dot: the table writes a plain h |
| гӀ | ġ | [ʁ] | the palochka Ӏ |
| къ | q̇ | [q’] | the hard sign ъ |
| цӀ | ċ | [ts’] | the palochka Ӏ |
| чӀ | ç̇ | [tʃ’] | the palochka Ӏ |
The dotted rows spell sounds with little in common, so the dot does not mark one sound. It marks a Cyrillic letter pair. хӀ is the one pair in the table without a dotted letter.
Wiktionary gives хьо (opens in a new tab), you, as /ˈħu̯o/. By the table it would be ẋo; that spelling is ours, letter by letter, not a quoted form. The table's own example is цхьаъ (opens in a new tab), one, which Wiktionary gives as /t͡sħaʔ/. The table prints it ċẋa’, with a dot on the c, although its list maps ц to a plain c.
Wiktionary dates this ẋ to 1992 to 2000 and calls it a letter of the Chechen Latin alphabet. The same Estonian table shows the older Roman alphabet of 1925 to 1937 writing that sound as x́, or x̌.
Why do x̌, x̱ and x̣ have no code point of their own?
Because Unicode builds that kind of x with accent from an x and a combining mark. The Unicode FAQ on combining marks (opens in a new tab) was asked to add precomposed letters for Navajo and other indigenous languages of the Americas. Its answer is to use combining marks. Its own example of a sequence that may display badly is an X with circumflex, U+0058 U+0302, and it blames the layout engine or the font, not the encoding.
The x with caron and the x with line below are just such letters, and they belong to living alphabets such as those of Tlingit, Kwak'wala and Heiltsuk. Wiktionary gives these uses in its entries for x̌ (opens in a new tab), x̱ (opens in a new tab), x̣ (opens in a new tab) and x̂ (opens in a new tab).
| Written | Built from | Language or system | Sound |
|---|---|---|---|
| x̌ | x + U+030C | Heiltsuk, Lushootseed, Okanagan; Kwak'wala in the Liqʼwala dialect | /χ/ |
| x̌ | x + U+030C | Wakhi, Shughni | /x/ |
| x̱ | x + U+0331 | Kwak'wala in the Uʼmista spelling, Squamish, Tlingit | /χ/ |
| x̱ | x + U+0331 | Haida | /ħ/ |
| x̣ | x + U+0323 | Nuu-chah-nulth; the North American Phonetic Alphabet | /χ/ |
| x̂ | x + U+0302 | Aleut, Haida | /χ/ |
Most rows spell /χ/, and each community picked its own mark for it. Kwak'wala uses two: x̱ in the standard Uʼmista spelling and x̌ in the Liqʼwala dialect. Tlingit sets x̱ /χ/ against a plain x /x/.
In our Node.js test on 2026-10-10, x plus each of these marks stayed two code points under NFC. Uppercasing gave X plus the same mark.
A character picker that searches by name finds ẋ and ẍ, but it has no entry for x̌ or any other x with accent built from a mark. Type the x, then add the mark. If the mark sits off-centre, the Unicode FAQ points to Doulos and Charis, fonts with large sets of such letters for linguists and minority languages.
How to type x with accent, step by step
Step 1: Word: type 1e8b, then press Alt+X
Type 1e8b where the letter belongs and press Alt+X to get ẋ. 1e8d gives ẍ, and the capitals are 1e8a for Ẋ and 1e8c for Ẍ. The same trick builds the x letters that have no code point: type x, then 030c, then press Alt+X for x̌.
Step 2: Mac: search the x by its Unicode name
Press Fn/Globe+E and search latin small letter x with dot above, or put diaeresis in place of dot above. Double-click the letter to place it.
Step 3: Windows: Win+., then the Symbols tab
Press Win+., open Symbols and scroll the Latin letters to the x group. Click ẋ or ẍ.
Step 4: In an equation, let LaTeX place the dots
For a derivative, write \dot{x} or \ddot{x}, and \dddot{x} once amsmath is loaded. Keep the encoded ẋ and ẍ for plain text, such as a filename, a chat message or a Chechen or Kurdish word.
What are all the x letters with accents?
Every x with an accent mark on AccentPad, lowercase then capitals. Tap one to copy it:
Which letters are related to x with accent?
These letter pages share an accent mark or a language with ẋ Ẋ ẍ Ẍ, the most shared languages first.
Every letter with the same mark, on one page, for ẍ: Umlaut.
ẋ Ẋ ẍ Ẍ have no Alt code: Windows cannot type them that way.
Need a letter other than ẋ?
Frequently asked questions about x with accent
Is the x with two dots an umlaut?
It carries the same mark. Unicode's names list gives U+0308, COMBINING DIAERESIS, the aliases double dot above, umlaut, Greek dialytika and double derivative. ẍ splits into x and that one code point whatever its job. In Kurdish the two dots voice the x into [ɣ]; in calculus they count a second derivative.
Does LaTeX need a package for three dots over an x?
Yes. LaTeX itself has \dot{x} and \ddot{x}. The amsmath user guide says the package adds \dddot and \ddddot for triple and quadruple dots. No single character holds either result, so a plain-text copy of \dddot{x} is an x followed by U+20DB, the mark Unicode's names list calls the third derivative.
What do Esperanto typists mean by cx, sx or ux?
They mean the x-system. Wiktionary describes it as a typing convention that drops the marks of ĉ, ĝ, ĥ, ĵ, ŝ and ŭ and writes an x after the bare letter: cx, gx, hx, jx, sx and ux. Its example is ambaux for ambaŭ. In that system the x replaces an accent instead of carrying one.
Is ᶍ, the x with a hook, an x with accent?
No. Unicode names U+1D8D LATIN SMALL LETTER X WITH PALATAL HOOK and gives it no decomposition, so no plain x and mark sit inside it. ẋ, by contrast, decomposes into x and U+0307. Wiktionary lists ᶍ as an obsolete IPA letter. Accent stripping through NFD leaves ᶍ as it is.
Will an accent-blind search for x also find ẋ and ẍ?
Yes. We compared them in Node.js v26.0.0 with ICU 78.3 on 2026-10-10 at base strength: ẋ and ẍ both equalled x under the English and the Kurdish rules. ICU has no rules for Chechen, Asturian or Mam; those locales fell back to en-US with the same result. An exact code-point match finds neither.