Co-articulated consonant
Co-articulated consonants or complex consonants are consonants produced with two simultaneous places of articulation. They may be divided into two classes: doubly articulated consonants with two primary places of articulation of the same manner, and consonants with secondary articulation; that is, a second articulation not of the same manner.
Doubly articulated consonants
An example of a doubly articulated consonant is the voiceless labial-velar stop, which is pronounced simultaneously at the velum and at the lips.In practically all languages of the world that have doubly articulated consonants, these are either clicks or labial-velars.
Consonants with secondary articulation
An example of a consonant with secondary articulation is the voiceless labialized velar stop has only a single stop articulation, velar, with a simultaneous approximant-like rounding of the lips.There is a large number of common secondary articulations. The most frequently encountered are labialization, palatalization, velarization, and pharyngealization.