ApproximantApproximants are speech sounds that involve the articulators approaching each other but not narrowly enough nor with enough articulatory precision to create turbulent airflow. Therefore, approximants fall between fricatives, which do produce a turbulent airstream, and vowels, which produce no turbulence. This class is composed of sounds like [ɹ] (as in rest) and semivowels like [j] and [w] (as in yes and west, respectively), as well as lateral approximants like [l] (as in less).
Nasal consonantIn phonetics, a nasal, also called a nasal occlusive or nasal stop in contrast with an oral stop or nasalized consonant, is an occlusive consonant produced with a lowered velum, allowing air to escape freely through the nose. The vast majority of consonants are oral consonants. Examples of nasals in English are [n], [ŋ] and [m], in words such as nose, bring and mouth. Nasal occlusives are nearly universal in human languages. There are also other kinds of nasal consonants in some languages.
Tap and flap consonantsIn 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 (such as the tongue) is thrown against another. The main difference between a tap or flap and a stop is that in a tap/flap there is no buildup of air pressure behind the place of articulation and consequently no release burst. Otherwise a tap/flap is similar to a brief stop. Taps and flaps also contrast with trills, where the airstream causes the articulator to vibrate.
VoicelessnessIn linguistics, voicelessness is the property of sounds being pronounced without the larynx vibrating. Phonologically, it is a type of phonation, which contrasts with other states of the larynx, but some object that the word phonation implies voicing and that voicelessness is the lack of phonation. The International Phonetic Alphabet has distinct letters for many voiceless and modally voiced pairs of consonants (the obstruents), such as [p b], [t d], [k ɡ], [q ɢ], [f v], and [s z].
Palato-alveolar consonantIn phonetics, palato-alveolar or palatoalveolar consonants are postalveolar consonants, nearly always sibilants, that are weakly palatalized with a domed (bunched-up) tongue. They are common sounds cross-linguistically and occur in English words such as ship and chip. The fricatives are transcribed ʃ (voiceless) and ʒ (voiced) in the International Phonetic Alphabet, while the corresponding affricates are tʃ (voiceless) and dʒ (voiced).
Retroflex consonantA retroflex (ˈɹɛtɹoʊflɛks or ˈɹɛtɹəflɛks), apico-domal, or cacuminal (kæˈkjuːmᵻnəl) consonant 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 Latin-derived word retroflex means "bent back"; some retroflex consonants are pronounced with the tongue fully curled back so that articulation involves the underside of the tongue tip (subapical).
Place of articulationIn articulatory phonetics, the place of articulation (also point of articulation) of a consonant is a location along the vocal tract where its production occurs. It is a point where a constriction is made between an active and a passive articulator. Active articulators are organs capable of voluntary movement which create the constriction, while passive articulators are so called because they are normally fixed and are the parts with which an active articulator makes contact.
Velar consonantVelars are consonants articulated with the back part of the tongue (the dorsum) against the soft palate, the back part of the roof of the mouth (also known as the “velum”). Since the velar region of the roof of the mouth is relatively extensive and the movements of the dorsum are not very precise, velars easily undergo assimilation, shifting their articulation back or to the front depending on the quality of adjacent vowels.
Alveolar consonantAlveolar (ælˈviːələr; UK also ælviˈoʊlər) consonants are articulated with the tongue against or close to the superior alveolar ridge, which is called that because it contains the alveoli (the sockets) of the upper teeth. Alveolar consonants may be articulated with the tip of the tongue (the apical consonants), as in English, or with the flat of the tongue just above the tip (the "blade" of the tongue; called laminal consonants), as in French and Spanish. The International Phonetic Alphabet (IPA) does not have separate symbols for the alveolar consonants.
IsoglossAn isogloss, also called a heterogloss (see Etymology below), is the geographic boundary of a certain linguistic feature, such as the pronunciation of a vowel, the meaning of a word, or the use of some morphological or syntactic feature. Major dialects are typically demarcated by bundles of isoglosses, such as the Benrath line that distinguishes High German from the other West Germanic languages and the La Spezia–Rimini Line that divides the Northern Italian languages and Romance languages west of Italy from Central Italian dialects and Romance languages east of Italy.