Systemic functional linguistics in the context of "Linguistic system"

Michael Alexander Kirkwood Halliday (often M. A. K. Halliday; 13 April 1925 – 15 April 2018) was a British linguist who developed the internationally influential systemic functional linguistics (SFL) model of language. His grammatical descriptions go by the name of systemic functional grammar. Halliday described language as a semiotic system, "not in the sense of a system of signs, but a systemic resource for meaning". For Halliday, language was a "meaning potential"; by extension, he defined linguistics as the study of "how people exchange meanings by 'languaging'". Halliday described himself as a generalist, meaning that he tried "to look at language from every possible vantage point", and has described his work as "wander[ing] the highways and byways of language". But he said that "to the extent that I favoured any one angle, it was the social: language as the creature and creator of human society".

Halliday's grammar differs markedly from traditional accounts that emphasise the classification of individual words (e.g. noun, verb, pronoun, preposition) in formal, written sentences in a restricted number of "valued" varieties of English. Halliday's model conceives grammar explicitly as how meanings are coded into wordings, in both spoken and written modes in all varieties and registers of a language. Three strands of grammar operate simultaneously. They concern (i) the interpersonal exchange between speaker and listener, and writer and reader; (ii) representation of our outer and inner worlds; and (iii) the wording of these meanings in cohesive spoken and written texts, from within the clause up to whole texts. Notably, the grammar embraces intonation in spoken language. Halliday's seminal Introduction to Functional Grammar (first edition, 1985) spawned a new research discipline and related pedagogical approaches. By far the most progress has been made in English, but the international growth of communities of SFL scholars has led to the adaptation of Halliday's advances to some other languages.

In linguistics, the term lexis (from Ancient Greek: λέξις 'word') designates the complete set of all possible words in a language, or a particular subset of words that are grouped by some specific linguistic criteria. For example, the general term English lexis refers to all words of the English language, while more specific term English religious lexis refers to a particular subset within English lexis, encompassing only words that are semantically related to the religious sphere of life.

In systemic-functional linguistics, a lexis or lexical item is the way one calls a particular thing or a type of phenomenon. Since a lexis from a systemic-functional perspective is a way of calling, it can be realised by multiple grammatical words such as "The White House", "New York City" or "heart attack". Moreover, since a lexis is a way of calling, different words such as child, children, child's and children's may realise the same lexical item.

Systemic functional grammar (SFG) is a form of grammatical description originated by Michael Halliday. It is part of a social semiotic approach to language called systemic functional linguistics. In these two terms, systemic refers to the view of language as "a network of systems, or interrelated sets of options for making meaning"; functional refers to Halliday's view that language is as it is because of what it has evolved to do (see Metafunction). Thus, what he refers to as the multidimensional architecture of language "reflects the multidimensional nature of human experience and interpersonal relations."

The term metafunction originates in systemic functional linguistics and is considered to be a property of all languages. Systemic functional linguistics is functional and semantic rather than formal and syntactic in its orientation. As a functional linguistic theory, it claims that both the emergence of grammar and the particular forms that grammars take should be explained "in terms of the functions that language evolved to serve". While languages vary in how and what they do, and what humans do with them in the contexts of human cultural practice, all languages are considered to be shaped and organised in relation to three functions, or metafunctions. Michael Halliday, the founder of systemic functional linguistics, calls these three functions the ideational, interpersonal, and textual. The ideational function is further divided into the experiential and logical.

Metafunctions are systemic clusters; that is, they are groups of semantic systems that make meanings of a related kind. The three metafunctions are mapped onto the structure of the clause. For this reason, systemic linguists analyse a clause from three perspectives. Halliday argues that the concept of metafunction is one of a small set of principles that are necessary to explain how language works; this concept of function in language is necessary to explain the organisation of the semantic system of language. Function is considered to be "a fundamental property of language itself".

Monosemy means 'one-meaning' and is a methodology primarily for lexical semantic analysis, but which has widespread applicability throughout the various strata of language.