A system of linguistic analysis developed by the American linguist Kenneth Lee Pike (1912—2000), and used by the Summer Institute of Linguistics for the training of linguists. Language is seen as comprising three modes – phonology, lexicon and grammar. The relationship phonology: phoneme and lexicon: morpheme is paralleled by grammar: tagmeme. This basic grammatical unit consists of a ‘functional slot’ within a construction frame, and a class of substitutable items that can fill this slot (‘fillers’). The identity of the tagmeme is in its correlation of function and form, with both being explicitly labelled in the analysis (such functions as subject, predicate, head, modifier and such forms as pronouns, noun phrases, infinitives). Tagmemic analysis involves a distinction between essential units ( the tagmemes) and the non-essential units (the minimal etic units, called tagmas, which are analysed as allotagmas of the tagmeme). The identification and classification of tagmas is the province of tagmatics. The constructions which result from the stringing together of tagmemes are known as syntagmemes. Grammatical units are organized hierarchically into levels (morphemes, words, phrases, clauses, sentences, etc.).

Units of language description, at any level in this approach, can be analysed simultaneously as particle (in terms of features), wave (in terms of their status as variants manifested in different contexts) and field (in terms of their distribution).