A fricative is a consonant produced by forcing air through a narrow channel made by placing two articulators close together. These may be the lower lip against the upper teeth, in the case of ; the back of the tongue against the soft palate in the case of German ; or the side of the tongue against the molars, in the case of Welsh. This turbulent airflow is called frication.
Phonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians. The field of phonetics is traditionally divided into three sub-disciplines based on the research questions involved such as how humans plan and execute movements to produce speech, how various movements affect the properties of the resulting sound, or how humans convert sound waves to linguistic information. Traditionally, the minimal linguistic unit of phonetics is the phone—a speech sound in a language which differs from the phonological unit of phoneme; the phoneme is an abstract categorization of phones, and it is also defined as the smallest unit that discerns meaning between sounds in any given language.
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, both of which are present in English. A third labial articulation is dentolabials, articulated with the upper lip against the lower teeth, normally only found in pathological speech. Generally precluded are linguolabials, in which the tip of the tongue contacts the posterior side of the upper lip, making them coronals, though sometimes, they behave as labial consonants.
Coronals are consonants articulated with the flexible front part of the tongue. Among places of articulation, only the coronal consonants can be divided into as many articulation types: apical, laminal, domed, or subapical as well as different postalveolar articulations : palato-alveolar, alveolo-palatal and retroflex. Only the front of the tongue (coronal) has such dexterity among the major places of articulation, allowing such variety of distinctions. Coronals have another dimension, grooved, to make sibilants in combination with the orientations above.
A dental consonant is a consonant articulated with the tongue against the upper teeth, such as, . In some languages, dentals are distinguished from other groups, such as alveolar consonants, in which the tongue contacts the gum ridge. Dental consonants share acoustic similarity and in Latin script are generally written with consistent symbols.
Alveolar consonants are articulated with the tongue against or close to the superior alveolar ridge, which is called that because it contains the alveoli of the upper teeth. Alveolar consonants may be articulated with the tip of the tongue, as in English, or with the flat of the tongue just above the tip, as in French and Spanish.
The field of articulatory phonetics is a subfield of phonetics that studies articulation and ways that humans produce speech. Articulatory phoneticians explain how humans produce speech sounds via the interaction of different physiological structures. Generally, articulatory phonetics is concerned with the transformation of aerodynamic energy into acoustic energy. Aerodynamic energy refers to the airflow through the vocal tract. Its potential form is air pressure; its kinetic form is the actual dynamic airflow. Acoustic energy is variation in the air pressure that can be represented as sound waves, which are then perceived by the human auditory system as sound.
Sibilants are fricative consonants of higher amplitude and pitch, made by directing a stream of air with the tongue towards the teeth. Examples of sibilants are the consonants at the beginning of the English words sip, zip, ship, and genre. The symbols in the International Phonetic Alphabet used to denote the sibilant sounds in these words are, respectively,. Sibilants have a characteristically intense sound, which accounts for their paralinguistic use in getting one's attention.
Labialization is a secondary articulatory feature of sounds in some languages. Labialized sounds involve the lips while the remainder of the oral cavity produces another sound. The term is normally restricted to consonants. When vowels involve the lips, they are called rounded.
Postalveolar or post-alveolar consonants are consonants articulated with the tongue near or touching the back of the alveolar ridge. Articulation is farther back in the mouth than the alveolar consonants, which are at the ridge itself, but not as far back as the hard palate, the place of articulation for palatal consonants. Examples of postalveolar consonants are the English palato-alveolar consonants, as in the words "ship", "'chill", "vision", and "jump", respectively.
A retroflex, apico-domal, or cacuminalconsonant is a coronal consonant where the tongue has a flat, concave, or even curled shape, and is articulated between the alveolar ridge and the hard palate. They are sometimes referred to as cerebral consonants—especially in Indology.
The bilabial clicks are a family of click consonants that sound like a smack of the lips. They are found as phonemes only in the small Tuu language family, in the ǂ’Amkoe language of Botswana, and in the extinct Damin ritual jargon of Australia. However, bilabial clicks are found paralinguistically for a kiss in various languages, including integrated into a greeting in the Hadza language of Tanzania, and as allophones of labial–velar stops in some West African languages, as of /mw/ in some of the languages neighboring Shona, such as Ndau and Tonga.
The voiced alveolar fricatives are consonantal sounds. The symbol in the International Phonetic Alphabet that represents these sounds depends on whether a sibilant or non-sibilant fricative is being described.
The voiced dental fricative is a consonant sound used in some spoken languages. It is familiar to English-speakers as the th sound in father. Its symbol in the International Phonetic Alphabet is eth, or and was taken from the Old English and Icelandic letter eth, which could stand for either a voiced or unvoiced (inter)dental non-sibilant fricative. Such fricatives are often called "interdental" because they are often produced with the tongue between the upper and lower teeth, and not just against the back of the upper teeth, as they are with other dental consonants.
In phonetics, a trill is a consonantal sound produced by vibrations between the active articulator and passive articulator. Standard Spanish ⟨rr⟩ as in perro, for example, is an alveolar trill.
In phonetics, a flap or tap is a type of consonantal sound, which is produced with a single contraction of the muscles so that one articulator is thrown against another.
Labial–velar consonants are doubly articulated at the velum and the lips, such as. They are sometimes called "labiovelar consonants", a term that can also refer to labialized velars, such as the stop consonant and the approximant.
An apical consonant is a phone produced by obstructing the air passage with the tip of the tongue (apex) in conjunction with upper articulators from lips to postalveolar, and possibly prepalatal. It contrasts with laminal consonants, which are produced by creating an obstruction with the blade of the tongue, just behind the tip. Sometimes apical is used exclusively for an articulation that involves only the tip of the tongue and apicolaminal for an articulation that involves both the tip and the blade of the tongue. However, the distinction is not always made and the latter one may be called simply apical, especially when describing an apical dental articulation. As there is some laminal contact in the alveolar region, the apicolaminal dental consonants are also labelled as denti-alveolar.
Palatals are consonants articulated with the body of the tongue raised against the hard palate. Consonants with the tip of the tongue curled back against the palate are called retroflex.
The voiceless alveolar nasal is a type of consonant in some languages. The symbols in the International Phonetic Alphabet that represent the sound are ⟨n̥⟩ and ⟨n̊⟩, combinations of the letter for the voiced alveolar nasal and a diacritic indicating voicelessness above or below the letter. The equivalent X-SAMPA symbol is n_0.
