Secondary articulation

Secondary articulation occurs when the articulation of a consonant is equivalent to the combined articulations of two or three simpler consonants, at least one of which is an approximant. The secondary articulation of such co-articulated consonants is the approximant-like articulation. It "colors" the primary articulation rather than obscuring it. Maledo (2011) defines secondary articulation as the superimposition of lesser stricture upon a primary articulation.

For example, the voiceless labialized velar plosive [kʷ] has a stop articulation, velar [k], with a simultaneous [w]-like rounding of the lips. This is in contrast to the doubly articulated labial-velar consonant [k͡p], which is articulated with two overlapping stop articulations.

There are a number of secondary articulations. The most frequently encountered are labialization (as with [kʷ]), palatalization (as with the Russian "soft" consonant [tʲ]), labio-palatalization (as in the name Twi), velarization (as with the English "dark" L [lˠ]), and pharyngealization (as with the Arabic "emphatic" consonant [tˤ]). It can be difficult to distinguish primary and secondary articulation. For example, the alveolo-palatal consonants [ɕ ʑ] are sometimes characterized as a primary articulation of their own and sometimes as palatalization of postalveolar fricatives, [ʃʲ ʒʲ] or [s̠ʲ z̠ʲ].

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