{{See also, grave and acute (phonetics) From an articulatory perspective,

phoneme In phonology and linguistics, a phoneme () is a unit of sound that can distinguish one word from another in a particular language. For example, in most dialects of English, with the notable exception of the West Midlands and the north-west o ...

s can be described as front or back.

Front vowel A front vowel is a class of vowel sounds used in some spoken languages, its defining characteristic being that the highest point of the tongue is positioned as far forward as possible in the mouth without creating a constriction that would otherw ...

s refer to vowels articulated towards the front of the mouth. This can either refer to vowels that are more front than

central Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

or, more rarely, only to fully front vowels, i.e. the ones that are articulated as far forward as possible in the mouth. A similar distinction holds for

back vowel A back vowel is any in a class of vowel sound used in spoken languages. The defining characteristic of a back vowel is that the highest point of the tongue is positioned relatively back in the mouth without creating a constriction that would be c ...

s, which can refer to vowels that are more back than central or, more rarely, only to fully back vowels, i.e. the ones that are articulated as back as possible in the mouth. However, acoustically there is little difference between a

central vowel A central vowel, formerly also known as a mixed vowel, is any in a class of vowel sound used in some spoken languages. The defining characteristic of a central vowel is that the tongue is positioned halfway between a front vowel and a back v ...

and a

, with the result that the two are frequently grouped together into an even broader category of "back vowels", or a category of "non-front vowels". A back consonant includes all consonants whose place of articulation is in the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...

(velum) or farther back, including velar, uvular, pharyngeal, and

glottal consonant Glottal consonants are consonants using the glottis as their primary articulation. Many phoneticians consider them, or at least the glottal fricative, to be transitional states of the glottis without a point of articulation as other consonants ...

s. From the perspective of primary places of articulation, this includes all of the laryngeal consonants and some of the

dorsal consonant Dorsal consonants are consonants articulated with the back of the tongue (the dorsum). They include the palatal, velar and, in some cases, alveolo-palatal and uvular consonants. They contrast with coronal consonants, articulated with the flexibl ...

s (specifically, excluding

palatal consonant Palatals are consonants articulated with the body of the tongue raised against the hard palate (the middle part of the roof of the mouth). Consonants with the tip of the tongue curled back against the palate are called retroflex. Characteristic ...

s). A front consonant includes all consonants that are not back consonants, including palatal, coronal, and

labial consonant Labial consonants are consonants in which one or both lips are the active articulator. The two common labial articulations are bilabials, articulated using both lips, and labiodentals, articulated with the lower lip against the upper teeth, bot ...

s. Front and back vowels are also known as acute and grave vowels, respectively. For consonants, however, front/back are not synonyms of acute/grave. Grave consonants include both back consonants and

labial consonants Labial consonants are consonants in which one or both lips are the active articulator. The two common labial articulations are bilabials, articulated using both lips, and labiodentals, articulated with the lower lip against the upper teeth, bot ...

, while acute consonants include all of front consonants ''except'' labial consonants. This suggests that a three-way division between labial, acute and back (vaguely speaking, "P-like", "T-like" and "K-like", respectively) might be useful in some contexts.

References

*Jacobson, Roman; ''On Language.''

Harvard University Press Harvard University Press (HUP) is a publishing house established on January 13, 1913, as a division of Harvard University, and focused on academic publishing. It is a member of the Association of American University Presses. After the retirem ...

, 1990 p. 260 Phonology