4.0 Historical aspects of the class
In 1900, no distinction was made between fricatives and approximants. Seven notions of approximants have been proposed since 1928, when fricatives and approximants were distinguished. Nearly a century ago, the class was first created; it was named approximant approximately forty years later. This section comprises three parts:
1. The description of the period between the creation of the class and the creation of the name approximant.
2. Two voiceless approximants [h] and [ʍ] played an important part in the constitution of the notion of approximant. [h] stood for other voiceless approximants. That is why this section more generally concerns all voiceless approximants.
3. It is surprising to realize that the name, once created, was applied to seven notions (six different notions). These notions are described and compared.
4.1 From the creation of the class to the creation of the name
In 1900, the Association Phonétique Internationale (1900: 7) does not distinguish, in its chart, any class corresponding to what will be called approximant. Semivowels are even considered fricatives. In 1928, Daniel Jones (1928: 23) created, in a chart (see Table 9), the class under the name of two components: Halbvokale and reibungslose Dauerlaute (semivowels and frictionless continuants).
Table 9. Semivowels and frictionless continuants according to Jones (1928).
1943. Central resonant orals and vocoids in Pike’s classifications. Pike (1943) classifies sounds according to two parameters: local friction and the resonance of the escape cavities.
The classification involving local friction distinguishes fricatives and resonants. Among resonants appear central resonant orals. Pike’s classification of resonants is illustrated in Figure 5 below (left side).
Then a distinction “according to the resonance of the escape cavities” permits to distinguish vocoids and contoids. “Vocoid and contoid groups are strictly delineated by the articulatory and acoustic nature of sounds, without reference to phonemic contextual function. The terms approximate current groupings of vowel and consonant in some of their major phonetics characteristics” (Pike 1943: 78).
Central resonants and vocoids are thus introduced in Pike’s classifications.
The first distinction emphasizes the contrast between fricatives and what will be called approximants. The second emphasizes their phonetic similarity with vowels.
As shown in Figure 5 (left side), the results of the two distinctions appear to be related. Vocoids are (with contoids) one of the two components of central resonants.
In 1964, Peter Ladefoged creates the name approximant. In his Phonetic Study of West African Languages, approximants cover central resonant orals and vocoids:
The term approximant is used here to describe a sound which belongs to the phonetic class vocoid or central resonant oral (Pike 1943), and simultaneously to the phonological class consonant in that it occurs in the same phonotactic patterns as stops, fricatives and nasals (Ladefoged 1964: 25)
4.2 Voiceless approximants
Two approximants were analyzed differently over time: [h] and [ʍ].
4.2.1 [h]
h]transcribed either a fricative or an approximant.
Traditionally, it corresponds to a fricative, according to Brücke’s (1876) description, cited by Kloster-Jensen (1991) and Livonen (1992).
In 1964, when the name approximant was created, [h] was considered a voiceless approximant, the voiceless equivalent of the subsequent sound, usually a vowel.
Ladefoged (1962: 107) describes [h] as a consonant whose articulator positions and acoustic characteristics are similar to those of the adjacent vowels, the difference lying in the vibration of the vocal folds.
The glottal approximant stands not only for a voiceless vowel but also, because of the predictable quality of the adjacent approximant, for a voiceless approximant consonant, as explained by Ladefoged (1975: 55-56) using the examples [hju] ‘hue’ and [hwitʃ] ‘which’.
Ladefoged (1990: 24) proposes placing the symbol [h] among ‘Other symbols’ of the IPA chart: “If the place of articulation of [h] is best left unspecified, then it should not be on the chart but should be listed under Other symbols as a ‘voiceless approximant’”.
Catford’s (1990: 26) opinion appears to be conclusive about the different aspects of [h]: “I am inclined to retain the status quo, letting [?], [h], and [ɦ] stay on the chart and calling them ‘fricatives’, with the implicit (or possibly explicit) proviso that these symbols may indicate either fricatives or approximants”.
His suggestion was not followed, and the examples are now transcribed as [j̞ju] and [ʍwitʃ].
4.2.2 [ʍ]
In Ladefoged’s (1964) and (1971) tables, [ʍ] was considered a labial velar approximant in the first table and a labial velar fricative in the second. The same example in Margi, [ʍàʍà] ‘boiled’, can be found in Ladefoged (1964: 65) and (1971: 15).
This example is borrowed from Hoffmann (1963), who provides a totally different description of the consonant appearing in the word. According to him, it is a “voiceless velar fricative (similar to Scottish loch, German lachen, phonetic symbol [x])” (Hoffmann 1963, §20) but “labialized” (§23). Therefore, instead of [ʍ], the sound appearing in the example is [xʷ], and the exact phonetic transcription of the example should be [xʷà xʷà]. This transcription corresponds to Ladefoged & Maddieson’s (1996: 326) description: “The voiceless counterpart of w cannot have friction at both the labial and velar places of articulation . . . so if it is a fricative, it is better described as a voiceless labialized velar fricative”.
The voiceless labial velar approximant [ʍ] is attested in eleven languages, according to Maddieson (1984: 247). It appears in Burmese, in [kuʍ] ‘swell up’, and in Klamath, Slovene, and Yao. [ʍ] is thus a voiceless labial velar approximant. As a fricative, only a voiceless labialized velar fricative is noted, [xʷ], contrary to what is indicated in the IPA charts.
4.3 The six first notions of approximant
In the thirty years between 1964 and 1994, six notions of approximant, though only five different ones, were proposed, first Ladefoged’s and Laver’s notions being the same, described in different terms.
4.3.1 1964: First, Ladefoged’s notion of approximant, with an explicit definition.
In the first notion, proposed by Ladefoged, as illustrated in Figure 6, approximants are voiced central resonant orals. As they belong to the class consonants, they are nonsyllabic. As there is no mention here of voiceless approximants, only voiced elements exist in the proposed class.
4.3.2 1964: Second, simultaneous with the first notion and implicit, Ladefoged’s notion of approximant.
As noted by Akamatsu (1992: 28), a notion of approximant, that contradicts the definition explicitly given in the same book, is implied by Ladefoged’s (1964) table 1. Two major differences from the other notion appeared: the presence of lateral approximants and of the approximant [h].
· Laterals. In Ladefoged’s (1964) table 1, two lateral approximants appeared: [l] and [λ]. In this implicit notion, an approximant is thus a sound that belongs to the phonetic class of resonant orals, comprising, according to Pike (1943), both central and lateral resonant orals.
· Voiceless consonants and vowels. Four voiceless central approximants appeared in the table: [ɹ̥], [ʍ], [ɥ̥] and [h]. [h], according to Ladefoged’s (1962: 107) description, stood in for a voiceless vowel.
The notion ensuing from Ladefoged’s (1964) table 1 was thus composed of four kinds of elements: central orals, lateral orals, voiceless consonants and voiceless vowels (as shown in Figure 6).
In 1967, Abercrombie (1967: 50) adopts the term approximant, corresponding to Ladefoged’s explicit definition.
4.3.3 1971: Ladefoged’s third notion of approximant.
This notion is attested to by two elements: a list of symbols given as an example and a ‘consonant chart’.
In Ladefoged (1971: 46), a short list of symbols provided as an example is composed of [a], [w], [l], and [ɹ]. This list shows that laterals and (voiced) vowels are included in the class.
The ‘consonant chart’ is provided in Ladefoged (1971: 122). The major change from the preceding chart of 1964 concerns voiceless approximants. Only [h] remains implicitly, according to Ladefoged (1975), standing in for any voiceless approximant (vowel or consonant). The three redundant (already represented by [h]) voiceless approximants [ɹ̥], [ʍ], and [ɥ̥] disappear from the chart.
This third notion of approximant is still in use in Ladefoged (1975). The same ‘consonant chart’ appears on the last page of A Course in Phonetics, and in the glossary, the following description can be found: “All vowels and (in many forms of English) /j, l, r, w/ are approximants”.
In this third notion, the class of approximants, according to Ladefoged, is made up of all oral resonants.
1975: Adoption by the IPA of the notion of approximant, corresponding to the 1964 implicit definition
In 1975, the IPA, through its secretary John Wells (1975: 54), adopts the term approximant: “I use Ladefoged’s convenient term ‘approximant’ to replace ‘frictionless continuant’”. However, even though it refers to Ladefoged (1971), as shown in the 1979 IPA chart (IPA 1978, see Table 9), it is the fourth original notion of approximants to be put forward. It is a class of central and lateral voiced oral consonants (no voiceless approximant appears in the chart).
· Laterals. In Ladefoged’s (1964) table 1, two lateral approximants appeared: [l] and [λ]. In this implicit notion, an approximant is thus a sound that belongs to the phonetic class of resonant orals, comprising, according to Pike (1943), both central and lateral resonant orals.
· Voiceless consonants and vowels. Four voiceless central approximants appeared in the table: [ɹ̥], [ʍ], [ɥ̥] and [h]. [h], according to Ladefoged’s (1962: 107) description, stood in for a voiceless vowel.
The notion ensuing from Ladefoged’s (1964) table 1 was thus composed of four kinds of elements: central orals, lateral orals, voiceless consonants and voiceless vowels (as shown in Figure 6).
In 1967, Abercrombie (1967: 50) adopts the term approximant, corresponding to Ladefoged’s explicit definition.
In 1975, the IPA, through its secretary John Wells (1975: 54), adopts the term approximant: “I use Ladefoged’s convenient term ‘approximant’ to replace ‘frictionless continuant’”. However, even though it refers to Ladefoged (1971), as shown in the 1979 IPA chart (IPA 1978, see Table 10), it is the fourth original notion of approximants to be put forward. It is a class of central and lateral voiced oral consonants (no voiceless approximant appears in the chart).
Table 10. Fricatives and approximants in the 1979 IPA chart
| Bilabial | Labiodental | Dental, alveolar, or postalveolar | Retroflex | Palatoalveolar | Palatal | Velar | Uvular | Labial-palatal | Labial-velar | Pharyngeal | Glottal | |
| (Median) Fricative | ɸ β | f v | θ ð s z | ʂ ʐ | ʃ ʒ | ç j | x ɣ | χ ʁ | ʍ | ħ ʕ | h ɦ | |
| (Median) Approximant | ʋ | ɹ | ɻ | j | ɰ | ɥ | w | |||||
| Lateral fricative | ɬ ɮ | |||||||||||
| Lateral (approximant) | l | ɭ | ʎ |
4.3.4 1977: Approximant according to Catford
Catford (1977: 122) borrows Ladefoged’s third notion but delimits the category of vowels “so as to exclude from it wide open front vowels of the type [ɛ, a], which are included in the next class of stricture”.
He determines three classes of strictures, the last one, which he calls resonant, comprising voiced, such as [ɛ], and voiceless, such as [ɛ̥], open front vowels.
Figure 4. Catford’s division of vowels into two groups, here called vowels 1 and 2.
According to Catford (1977: 122), the class of approximants is composed of vowels other than “wide open front vowels of the type [ɛ, a]” and of central and lateral nonturbulent (when voiced) consonants.
Vowels are thus divided into two parts, here called vowels 1 and vowels 2, the first constituting the approximants and the second being the resonants in Catford’s terminology, the third class distinguished by Catford. This is illustrated in Figure 4.
In Catford’s notion, the class of approximants is made up of all oral resonants except voiceless and voiced vowels 2 (wide open front vowels).
4.3.5 1994: Approximant according to Laver.
Laver defines an approximant as a nonsyllabic noncontoid central resonant.
For Ladefoged (1964, 25), an approximant is a vocoid belonging to the phonological class consonant, and Laver defines it as a nonsyllabic noncontoid.
Laver calls noncontoid what Pike (1943) and Ladefoged (1964) call a vocoid, and among these noncontoids, he makes a distinction, according to a criterion of syllabicity, between the syllabic ones, called the vocoids, and the nonsyllabic ones, called the approximants. This distinction is illustrated in Figure 5.
Figure 5. Classifications of resonants according to Pike (1943), Ladefoged (1964) and Laver (1994).
Laver’s class of sounds thus defined and called approximant corresponds to Ladefoged’s first notion of approximant but with different terms.
4.4. The seventh and last notion of approximant
Gradually, voiceless approximants were described, and even though they do not appear in the latest IPA chart because of their notation with a diacritic, they nevertheless exist. As they are described as illustrations of the IPA, they are admitted by the IPA; for example, [ɹ̥] and [l̥] are described in Tianjin Mandarin by Li et al. (2019). There is thus a seventh notion of approximant with voiced and voiceless lateral and central oral resonants.
Figure 6. The seven notions of approximant that appeared between 1964 (1928) and 2020. Wide open front vowels, distinguished by Catford (1977), are here called vowels 2, and the other vowels are called vowels 1.
4.5 Summary of the historical aspects of the class
As shown in Figure 6, the difference between the first and last notions of approximants can be summarized in two words: laterality and voicing. The first notion comprised only voiced central approximants; voiceless and lateral approximants completed the last notion. Between these two states, the most noticeable difference is the temporary presence of voiced and voiceless vowels. The number of intermediary states proves the difficulty in developing the notion. the class of approximants, according to Ladefoged, is made up of all oral resonants.