Morphotactics represent the ordering restrictions in place on the ordering of

morphemes A morpheme is the smallest meaningful constituent of a linguistic expression. The field of linguistic study dedicated to morphemes is called morphology. In English, morphemes are often but not necessarily words. Morphemes that stand alone a ...

. Etymologically, it can be translated as "the set of rules that define how morphemes (morpho) can touch (tactics) each other".

Example of a morphotactic rule

Many English

affix In linguistics, an affix is a morpheme that is attached to a word stem to form a new word or word form. Affixes may be derivational, like English ''-ness'' and ''pre-'', or inflectional, like English plural ''-s'' and past tense ''-ed''. They ar ...

es may only be attached directly to morphemes with particular

parts of speech In grammar, a part of speech or part-of-speech (abbreviated as POS or PoS, also known as word class or grammatical category) is a category of words (or, more generally, of lexical items) that have similar grammatical properties. Words that are assi ...

: * '' do'' + ''

-able In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns, adjectives, and verb endings, which form the conjugation of verbs. Suffixes can carry gr ...

'' + '' -ity'' = '' doability'' but not * '' do'' + '' -ity'' + ''

'' = *''doityable'' The suffix '' -ity'' produces a noun from an adjective, and ''

'' creates

adjectives In linguistics, an adjective (abbreviated ) is a word that generally modifies a noun or noun phrase or describes its referent. Its semantic role is to change information given by the noun. Traditionally, adjectives were considered one of the mai ...

from verbs.{{Cite web, url=http://www-rohan.sdsu.edu/~gawron/compling/week3/morph.htm, title = Computational Linguistics To reverse the order violates the rules of English morphotactics, making the word

ungrammatical In linguistics, grammaticality is determined by the conformity to language usage as derived by the grammar of a particular speech variety. The notion of grammaticality rose alongside the theory of generative grammar, the goal of which is to form ...

(marked with an

asterisk The asterisk ( ), from Late Latin , from Ancient Greek , ''asteriskos'', "little star", is a typographical symbol. It is so called because it resembles a conventional image of a heraldic star. Computer scientists and mathematicians often voc ...

Common morphotactic model

Finite-state machine A finite-state machine (FSM) or finite-state automaton (FSA, plural: ''automata''), finite automaton, or simply a state machine, is a mathematical model of computation. It is an abstract machine that can be in exactly one of a finite number o ...

and

Graph Graph may refer to: Mathematics *Graph (discrete mathematics), a structure made of vertices and edges **Graph theory, the study of such graphs and their properties *Graph (topology), a topological space resembling a graph in the sense of discre ...

are the two models which are often used as a set of rules for morphotactics.

References

* ''Morphology and Computation,'' By Richard William Sproat. MIT Press: 1992, p. 83

* ''Finite-state non-concatenative morphotactics'' By Kenneth R. Beesley and Lauri Karttunen 2000. In Proceedings of the 38th Annual Meeting on

Association for Computational Linguistics The Association for Computational Linguistics (ACL) is a scientific and professional organization for people working on natural language processing. Its namesake conference is one of the primary high impact conferences for natural language proces ...

(ACL '00). Association for Computational Linguistics ;Notes Grammar