Obsolete and nonstandard symbols in the International Phonetic Alphabet

The International Phonetic Alphabet (IPA) possesses a variety of obsolete and nonstandard symbols. Throughout the history of the IPA, characters representing phonetic values have been modified or completely replaced. An example is ⟨ɷ⟩ for standard [ʊ]. Several symbols indicating secondary articulation have been dropped altogether, with the idea that such things should be indicated with diacritics: ʮ for z̩ʷ is one. In addition, the rare voiceless implosive series ƥ ƭ ƈ ƙ ʠ has been dropped.

Other characters have been added in for specific phonemes which do not possess a specific symbol in the IPA. Those studying modern Chinese phonology have used ⟨ɿ⟩ to represent the sound of -i in Pinyin hanzi which has been variously described as [ɨ], [ɹ̩], [z̩] or [ɯ]. (See the sections Vowels and Syllabic consonants of the article Standard Chinese phonology.)

There are also unsupported symbols from local traditions that find their way into publications that otherwise use the standard IPA. This is especially common with affricates such as ƛ, and many Americanist symbols.

While the IPA does not itself have a set of capital letters (the ones that look like capitals are actually small capitals), many languages have adopted symbols from the IPA as part of their orthographies, and in such cases they have invented capital variants of these. This is especially common in Africa. An example is Kabiyé of northern Togo, which has Ɔ Ɛ Ŋ Ɣ. Other pseudo-IPA capitals supported by Unicode are Ɓ/Ƃ Ƈ Ɗ/Ƌ Ə/Ǝ Ɠ Ħ Ɯ Ɲ Ɵ Ʃ (capital ʃ) Ʈ Ʊ Ʋ Ʒ. (See Case variants of IPA letters.)

Capital letters are also used as cover symbols in phonotactic descriptions: C=Consonant, V=Vowel, etc.

This list does not include commonplace extensions of the IPA, such as doubling a symbol for a greater degree of a feature ([aːː] extra-long [a], [ˈˈa] extra stress, [kʰʰ] strongly aspirated [k], and [a˞˞] extra-rhotic [a]), nor superscripting for a lesser degree of a feature ([ᵑɡ] slightly prenasalized [ɡ], [ᵗs] slightly affricated [s], and [ᵊ] epenthetic schwa). The asterisk, as in [k*] for the fortis stop of Korean, is the convention the IPA uses when it has no symbol for a phone or feature.

For symbols and values which were discarded by 1932, see History of the International Phonetic Alphabet.

Obsolete and/or nonstandard symbols in the International Phonetic Alphabet

Symbol or exemplar	Name	Meaning	Standard IPA equivalent	Notes
?	question mark	glottal stop	ʔ	typewriter substitution
7	digit seven
ƍ	turned small delta	a voiced "labialized" alveolar or dental fricative	ðʷ, zʷ, z͎	Intended for the voiced whistled sibilant, ɀ, of Shona and related languages
σ	small sigma	a voiceless "labialized" alveolar or dental fricative	θʷ, sʷ, s͎	Intended for the voiceless whistled sibilant, ȿ, of Shona and related languages
ƺ	ezh with tail	labialized voiced postalveolar fricative	ʒʷ, ʑᶣ	Intended for w before front vowels in Twi; may also be used for the lightly rounded English /ʒ/.
ƪ	reversed esh with top loop	labialized voiceless postalveolar fricative	ʃʷ, ɕᶣ	Intended for hw before front vowels in Twi; may also be used for the lightly rounded English /ʃ/.
ƻ	barred two	voiced alveolar affricate	d͡z	withdrawn 1976
ƾ	rotated epiglottal plosive (actually a vertical ts ligature)	voiceless alveolar affricate	t͡s	withdrawn 1976
ƞ	right-leg N (Latin eta, very similar to the lowercase Greek letter eta (η))	moraic ("syllabic") nasal	m, n, ŋ	Intended for the moraic nasal /N/ of Japanese. withdrawn 1976
ᶀ ᶁ ᶂ ᶃ ᶄ ᶅ ᶆ ᶇ ᶈ ᶉ ᶊ ᶋ ƫ ᶌ ᶍ ᶎ	letters with left hook	palatalization	bʲ dʲ fʲ ɡ̟ k̟ lʲ mʲ nʲ pʲ rʲ sʲ ʃʲ tʲ vʲ x̟ zʲ	Typically used in the transcription of Slavic languages such as Russian. superseded 1989
	double-loop g	voiced velar fricative	ɣ	From 1895 to 1900, [q] represented that consonant before 1895, [ǥ] after 1900
		voiced velar plosive	ɡ	The standard Unicode Basic Latin/ASCII lower-case g (U+0067) may have a double-loop g glyph. The preferred IPA single-loop g (U+0261) is in the IPA Extensions Unicode block. For a time it was proposed that the double-loop g might be used for [ɡ] and the single-loop g for [ᶃ] (ɡ̟), but the distinction never caught on.
	single-loop g with stroke	voiced velar fricative	ɣ	Superseded double-loop g in 1900, superseded by gamma [ɣ] between 1928 and 1930. The character ǥ may not have the single-loop shape in some fonts.
k̫ etc.	subscript w	labialization	kʷ etc.	Diacritic may appear above letters with descenders such as [ɡ] and [ŋ]. superseded 1989
ʓ	curly-tail ezh	voiced alveolo-palatal(ized) fricative	ʒʲ	Irregular, instead of ⟨ʒ⟩ with a tail. withdrawn 1989
ʆ	curly-tail esh	voiceless alveolo-palatal(ized) fricative	ʃʲ	Irregular, instead of ⟨ʃ⟩ with a tail. Used for Russian щ (now ⟨ɕ⟩). withdrawn 1989
ř	r with caron	voiced strident apico-alveolar trill	r̝	Intended for ř in Czech and related languages. ⟨ř⟩ from 1909, replaced by ⟨ɼ⟩ in 1949, withdrawn 1989
ɼ	long-leg r
λ	lambda	voiced alveolar lateral affricate	d͡ɮ	Used by Americanists
ƛ	barred lambda	voiceless alveolar lateral affricate	t͡ɬ	Used by Americanists
ł	lowercase L with stroke	voiceless alveolar lateral fricative	ɬ	Used by Americanists
š č ž	s c z with caron	postalveolars	ʃ t͡ʃ ʒ; ʂ tʂ ʐ	Used by Americanists, Uralicists, Semiticists, Slavicists
ǰ, ǧ, ǯ	j, g, ezh with caron	voiced postalveolar affricate	d͡ʒ	Used by Americanists, Slavicists etc.
ẋ	x with dot	voiceless uvular fricative	χ	Used by Americanists
	baby gamma	close-mid back unrounded vowel	ɤ	rejected 1989; Unicode LATIN SMALL LETTER RAMS HORN (U+0264) represents either glyph
ρ	Greek rho	bilabial trill	ʙ	in common use before an official letter was adopted
ᵻ / ᵿ	barred small capital I / upsilon	near-close central unrounded / rounded vowel	ɨ̞ / ʉ̞	used by the OED among others
ʚ	closed epsilon	open-mid front rounded vowel	œ	duplicate symbol (from 1904 until the 1920s)
		open-mid central rounded vowel	ɞ	superseded 1996
ɷ	closed omega	near-close near-back rounded vowel	ʊ	longstanding duplicate symbol; rejected 1989
ω	omega	near-close near-back unrounded vowel	ʊ̜ or ɯ̽	Bloch & Trager (1942) for [ɒ̝].
ɩ	small iota	near-close near-front unrounded vowel	ɪ	Longstanding duplicate symbol; rejected 1989
ı	dotless small i	near-close near-front unrounded vowel	ɪ	mistake or typographic substitute
ȹ ȸ		voiceless and voiced labiodental plosive	p̪ b̪	used by Africanists
∅ or Ø	slashed 0 or uppercase slashed O	null initial		Usually used in phonology to mean "no sound values". However, in Chinese linguistics, some scholars considered it as "weak" glottal stop or something similar as sound value of the "existent" first consonant of syllables started by a vowel (e.g. ān in Tiān'ānmén), and this opinion can be connected with ㅇ (ieung) in hangul. ∅ can be confusing with close-mid front rounded vowel [ø].
ƥ ƭ ƈ ƙ ʠ	hooktop P, T, C, K, Q	voiceless implosives	ɓ̥ ɗ̥ ʄ̊ ɠ̊ ʛ̊	Short-term additions to the IPA; withdrawn 1993
ʇ	turned T	dental click	ǀ	superseded 1989; see click letters
ʗ	stretched C	alveolar click	ǃ	superseded 1989; see click letters
ʖ	inverted glottal stop	alveolar lateral click	ǁ	superseded 1989; see click letters
ʞ	turned K	velar click		Proposed symbol withdrawn 1970; articulation judged impossible but later reanalyzed and found paralinguistically. For several years used for a voiceless velodorsal stop in the extIPA.
ȣ	ou	close-mid back unrounded vowel or voiced velar fricative	ɤ or ɣ	a mistake in either case
я	reversed ʀ or Cyrillic ya	voiced epiglottal trill	ʀ̠ or ʢ	rare
ɿ	reversed fishhook R / turned iota	high back unrounded vowel, with frication from the preceding consonant	◌͡ɯ	used by Sinologists, and by Japanologists studying the phonology of the Miyako language
ʅ	squat reversed esh (actually ɿ with retroflex tail)	high central unrounded vowel, with frication from the preceding consonant	◌͡ɨ	used by Sinologists. See Chinese vowels
ʮ	turned h with fishhook	high back rounded vowel, with frication from the preceding consonant	◌͡u	used by Sinologists
ʯ	turned h with fishhook and tail	high central rounded vowel, with frication from the preceding consonant	◌͡ʉ	used by Sinologists
ᴀ	small capital A	open central vowel	ä, a̱, ɑ̈, ɑ̟, ɐ̞	used by Sinologists
ᴇ	small capital E	mid front unrounded vowel	e̞, ɛ̝	Bloch & Trager (1942). Used by Sinologists and some Koreanists
ⱻ	small capital turned E	close-mid near-back unrounded vowel	ɤ̘	used by some Koreanists who study Gyeongsang dialect, where there is no phonemic differentiation between /ʌ/ (RR eo; Hangul ㅓ) and /ɯ/ (RR eu; Hangul ㅡ).
ꭥ	small capital Ω	mid back rounded vowel	o̞, ɔ̝	Bloch & Trager (1942)
ᴜ	small capital U	near-close near-back rounded vowel	ʊ, ʊ̹	Americanist notation
G R Œ etc.	uppercase letters		ɢ ʀ ɶ etc.	Uppercase alternatives to symbols shaped like small capitals
ꞯ	small capital Q		ʡ	Proposed for the pharyngeal stop of Formosan languages.
ꞎ  	belted	Voiceless lateral fricatives (retroflex, palatal and velar)	ɭ̥˔ ʎ̥˔ ʟ̥˔	now in the extIPA
		Retroflex lateral flap	ɭ̆
ɑ̣ etc.	underdot	("retroflex" or r-colored vowels)	ɑ˞ etc.
ȡ ȶ ȵ ȴ etc., d̂ t̂ n̂ l̂ etc.	curl or circumflex	alveolo-palatal	d̠ʲ t̠ʲ n̠ʲ l̠ʲ etc.	used by Sinologists
k', etc.		no audible release	k̚, etc.	Withdrawn
K P T etc.	uppercase letters (not small capitals)	fortis	k͈ p͈ t͈, etc.	used by some Koreanists
ɔ̗ / ɔ̖ etc.		lower-pitched rising / falling tone contour		In a language which distinguishes more than one rising or falling tone.
k‘ t‘, kʻ tʻ	left quote or reversed comma	"weak" (sometimes "normal") aspiration	k t (sometimes kʰ tʰ)	First symbol may be left single quotation mark (U+2018) or modifier letter apostrophe (U+02BC); second symbol may be single high-reversed-9 quotation mark (U+201B) or modifier letter reversed comma (U+02BD)
ʦ ʣ ʧ ʤ etc.	ligatures	affricates	ts dz tʃ dʒ etc., t͡s d͡z t͡ʃ d͡ʒ etc.	Formerly an acceptable variant
p′ etc.	prime	palatalization	pʲ etc.	Traditional in accounts of Irish phonology
*	asterisk	syntactic gemination	none	Used in some Italian dictionaries
˹	open corner	release/burst	(none)	IPA number 490
c or ȼ	[	Americanist notation
ʒ	[	Americanist notation
y	[	Americanist notation
ä	[ or [	Uralicist notation
ö	[	Americanist and Uralicist notation
ü	[	Americanist and Uralicist notation
k’ etc.	Used by some Koreanists for fortis sounds; equivalent to ⟨k*⟩, etc. above.
◌⸋	box	unreleased	◌̚	used where IPA ◌̚ would get confused with the corners used to indicate change of pitch in the Japanese pitch accent system
ˉ◌, ˗◌, ˍ◌	high, mid and low-level tone or intonation	superseded	⟨◌⟩ is a placeholder
˭◌, ₌◌	extra-high and extra-low level tone or intonation	superseded
ˋ◌, ˴◌, ˎ◌	falling or high falling, mid falling and low-falling tone or intonation	superseded
ˊ◌, ˏ◌	(high) rising and low rising tone or intonation	superseded
ˇ◌, ˬ◌	(high) dipping and low dipping (falling-rising) tone or intonation	superseded
ˆ◌	peaking (rising-falling) tone or intonation	superseded
˙◌, ·◌, .◌	atonic syllable with high, mid and low pitch	superseded

The table below shows examples of expansion in the meaning of IPA symbols in broad transcription.

c	[ or [.
ɟ	[ or [.
r	Frequently used for any rhotic sound (including R-colored vowels), especially in phonological transcriptions.
a	Often a substitute for < in printing when the distinction between [ and [ is not needed.
ɑ	Often a substitute for < in handwriting when the distinction between [ and [ is not needed.
ʃ ʒ t͡ʃ d͡ʒ	<, <, <, and < respectively, especially by some Japanologists and Koreanists.

See also

• History of the IPA
• Americanist phonetic notation
• Uralic Phonetic Alphabet