In linguistics, the term double articulation or duality of patterning refers to the way in which the stream of speech can be divided into meaningful signs, which can be further subdivided into meaningless elements. So for example, the meaningful English word "cat" is composed of the sounds [k], [æ], and [t], which are meaningless as separate individual sounds (and which can also be combined to form the separate words "tack" and "act", with distinct meanings). According to Charles F. Hockett

Charles F. Hockett

Charles Francis Hockett was an American linguist who developed many influential ideas in American structuralist linguistics. He represents the post-Bloomfieldian phase of structuralism often referred to as "distributionalism" or "taxonomic structuralism"...

 and other linguists, this is an important property of human languages, since it allows for the expression of a large number of meaningful language sequences using combinations of a small number of discrete sound elements or phonemes. For further discussion, see figurae

Figurae

Figurae are the non-signifying constituents of signifiers . For example, letters of the alphabet are the figurae that comprise a written word . In the semiotic language of Louis Hjelmslev, the coiner of this term, figurae serve only to distinguish elements of the expression plane from each...

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For consonants with two simultaneous primary places of articulation, see doubly articulated consonant

Doubly articulated consonant

Doubly articulated consonants are consonants with two simultaneous primary places of articulation of the same manner . They are a subset of co-articulated consonants. They are to be distinguished from co-articulated consonants with secondary articulation, that is, a second articulation not of the...

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