In phonetics, secondary articulation occurs when the articulation of a consonant is equivalent to the combined articulations of two or three simpler consonants, at least one of which is an approximant. The secondary articulation of such co-articulated consonants is the approximant-like articulation. It "colors" the primary articulation rather than obscuring it. Maledo (2011) defines secondary articulation as the superimposition of lesser stricture upon a primary articulation.
Types of secondary articulation
There are several kinds of secondary articulation supported by the International Phonetic Alphabet.
- labialization. This is the most frequently encountered secondary articulation. For example, labialized [kʷ] has a primary velar plosive articulation, [k], with simultaneous [w]-like rounding of the lips. (Thus the name 'labialization'.) This is in contrast to the doubly articulated labial-velar consonant [k͡p], which is articulated with two overlapping plosive articulations, [k] and [p].
- palatalization. This is perhaps best known from the Russian "soft" consonants like [tʲ]), which is has a primary alveolar plosive articulation, [t], with simultaneous [j]-like (i.e. y-like) raising of the body of the tongue.
- labio-palatalization. This simultaneous labialization and palatalization. It's found for example in the name Twi.
- velarization. This is the raising of the back of the tongue toward the velum, as in the English "dark" L, [lˠ].
- pharyngealization. This is a constriction in the throat (pharynx), as with the Arabic "emphatic" consonants such as [tˤ].
- glottalization. This involves action of the glottis in addition to the primary articulation of the consonant.
It can sometimes be difficult to distinguish primary and secondary articulation. For example, the alveolo-palatal consonants [ɕ ʑ] are sometimes characterized as a primary articulation of their own and sometimes as palatalization of postalveolar fricatives, [ʃʲ ʒʲ] or [s̠ʲ z̠ʲ].
The most common method of transcription in the IPA is to turn the letter corresponding to the secondary articulation into a superscript written after the letter for the primary articulation. For example, the w in ⟨kʷ⟩ is written after the k. This can be misleading, as it iconically suggests that the [k] is released into a [w] sound, analogous to ⟨kˡ kⁿ⟩ ([k] with a lateral and nasal release), when actually the two articulations of [kʷ] are generally pronounced more-or-less simultaneously. Secondary articulation often has a strong effect on surrounding vowels, and may have an audible realization that precedes the primary consonant, or both precedes and follows it. For example, /akʷa/ will not generally sound simply like [akwa], but may be closer to [awkwa] or even [awka]. For this reason, the IPA symbols for labialization and palatalization were for a time placed under the primary letter (e.g. ⟨k̫⟩ for [kʷ] and ⟨ƫ⟩ for [tʲ]), and a number of phoneticians still prefer such unambiguous usage, with ⟨kʷ⟩ and ⟨tʲ⟩ used specifically for off-glides, despite the official policy of the IPA. In the official IPA there remains only an alternative symbol for velarization/pharyngealizaton that is superposed over the primary (e.g. ⟨ɫ⟩ for dark L), but it has font support for a limited number of consonants and is inadvisable for others, where it can be illegible.
There is a longstanding tradition in the IPA that one may turn any IPA letter into a superscript, and in so doing impart its features to the base consonant. For instance, [ʃˢ] would be an articulation of [ʃ] that has qualities of [s]. However, the features are not necessarily imparted as secondary articulation. Superscripts are also used iconically to indicate the onset or release of a consonant, the on-glide or off-glide of a vowel, and fleeting or weak segments. Among other things, these phenomena include pre-nasalization ([ᵐb]), pre-stopping ([ᵖm, ᵗs]), affrication ([tᶴ]), pre-affrication ([ˣk]), trilled, fricative, nasal, and lateral release ([tʳ, tᶿ, dⁿ, dˡ]), rhoticization ([ɑʵ]), and diphthongs ([aᶷ]). So, while ⟨ˠ⟩ indicates velarization of non-velar consonants, it is also used for fricative release of the velar stop (⟨ɡˠ⟩). Mixed consonant-vowels may indicate a transition: [ᵇa] may be the allophone of /a/ with the transition from /b/ that identifies the consonant, while [fʸ] may be the allophone of /f/ before /y/, or the formants of /y/ anticipated in the /f/.
The 2015 edition of the Extensions to the International Phonetic Alphabet formally advocates superscript letters for the first time since 1989, specifically for the release of plosives.
Unicode support of superscript IPA letters
The customary use of superscript IPA letters, advocated in IPA charts until 1989, is formalized again in the extIPA chart of 2015. However, not all regular IPA letters and no extIPA letters are supported by Unicode. No non-pulmonic consonants are supported, nor are the length marks, though these may be found in print (for example, long aspiration may be transcribed as superscript ⟨h⟩ followed by superscript ⟨ː⟩). The regular IPA letters that are supported by Unicode as of 2019 are as follows. Letters in grey are not supported. Letters in orange are not properly supported but can be substituted. These superscript letters can be modified by IPA and extIPA diacritics, just as full letters are. For example, a superscript dental nasal would be ⟨ⁿ̪⟩. In a good font the diacritic will align properly with the superscript letter.
There are no superscript implosive, click or ExtIPA letters, except accidentally with ⟨ꜝ⟩, ⟨ꜞ⟩, nor ⟨ɧ⟩, all of which can be found in print. With a properly designed font, combining diacritics (such as the bridge for dental consonants, as above, or the ring for voicelessness) will work with superscript letters, as in ⟨ᵑ̊ǃ⟩. So does the ejective spacing diacritic: ⟨ᵖʼ ᵗʼ ᶜʼ ᵏʼ⟩. Spacing diacritics, however, as in ⟨tʲ⟩, cannot be secondarily superscripted through hard coding: ⟨ᵗʲ⟩.
|Close||i ⁱ||y ʸ||ɨ ᶤ||ʉ ᶶ||ɯ ᵚ||u ᵘ|
|Near-close||ɪ ᶦ||ʏ ⁻||ᵻ ᶧ||ᵿ ⁻||ʊ ᶷ|
|Close-mid||e ᵉ||ø ⁻||ɘ ⁻||ɵ ᶱ||ɤ ⁻||o ᵒ|
|Open-mid||ɛ ᵋ||œ ꟹ||ɜ ᶟ||ɞ ⁻||ʌ ᶺ||ɔ ᵓ|
||ɶ ⁻||ɐ ᵄ||ɑ ᵅ||ɒ ᶛ|
The three superscript mid central vowels correspond to the complete set of mid central vowels in the IPA immediately after the 1989 Kiel Convention. The two vowel added later are not supported as of 2019.
The precomposed rhotic vowels ⟨ɚ ɝ⟩ are not supported, but the rhotic spacing diacritic works fairly well on superscript vowels despite not being superscripted itself: ⟨ᵊ˞ ᵌ˞ ᵋ˞ ᵓ˞ ᵅ˞⟩. Combining diacritics work as normal, though in some fonts the nasal tilde for example may be notably wider than the vowel it modifies: ⟨ᵓ̃⟩.
- International Phonetic Association (1978). "The International Phonetic Alphabet (Revised to 1979)". Journal of the International Phonetic Association. 8 (1–2). Supplement. JSTOR 44541414. Reprinted in MacMahon (2010), p. 271.
- Ball, Martin J.; Howard, Sara J.; Miller, Kirk (2018). "Revisions to the extIPA chart". Journal of the International Phonetic Association. 48 (2): 155–164. doi:10.1017/S0025100317000147.
- Superscript ⟨ç⟩ composed of superscript c and a combining cedilla; it will not display properly in all fonts.
- ⟨ᵸ⟩ is actually a superscript lower-case Cyrillic ⟨н⟩, but is graphically identical to superscript IPA ⟨ʜ⟩ (assuming a font that handles both).
- This is actually a superscript el with 'lazy s', ⟨ꬷ⟩, used in German dialectology.
- ⟨ᵆ⟩ is actually a superscript turned æ, but except at large font sizes the difference is not easily visible.