A morpheme is the smallest meaningful unit in a language. A morpheme is not necessarily the same as a word. The main difference between a morpheme and a word is that a morpheme sometimes does not stand alone, but a word, by definition, always stands alone. The field of linguistic study dedicated to morphemes is called morphology. When a morpheme can stand alone, it is considered a root because it has a meaning of its own (such as the morpheme ''cat''). When it depends on another morpheme to express an idea, it is an affix because it has a grammatical function (such as the ''–s'' in ''cats'' to indicate plurality). Every word is composed of one or more morphemes.

Classification of morphemes

Free and bound morphemes

Free and morphemes

Every morpheme can be classified as either free or bound. Since the categories are mutually exclusive, a given morpheme will belong to exactly one of them. * Free morphemes can function independently as words (e.g. ''town'', ''dog'') and can appear within lexemes (e.g. ''town hall'', ''doghouse''). * Bound morphemes appear only as parts of words, always in conjunction with a root and sometimes with other bound morphemes. For example, ''un-'' appears only accompanied by other morphemes to form a word. Most bound morphemes in English are affixes, particularly prefixes and suffixes. Examples of suffixes are ''-tion'', ''-sion'', ''-tive'', ''-ation'', ''-ible'', and ''-ing''. Bound morphemes that are not affixed are called cranberry morphemes.

Classification of bound morphemes

Bound morphemes can be further classified as derivational or inflectional morphemes. The main difference between derivational morphemes and inflectional morphemes is their function in relation to words.

= Derivational Bound morphemes


Derivational morphemes

* Derivational morphemes, when combined with a root, change the semantic meaning or the part of speech of the affected word. For example, in the word ''happiness'', the addition of the bound morpheme ''-ness'' to the root ''happy'' changes the word from an adjective (''happy'') to a noun (''happiness''). In the word ''unkind'', ''un-'' functions as a derivational morpheme since it inverts the meaning of the root morpheme (word) ''kind''. Generally, morphemes that affix (i.e., affixes) to a root morpheme (word) are bound morphemes.

= Inflectional bound morphemes


Inflectional morphemes

* Inflectional morphemes modify the tense, aspect, mood, person, or number of a verb, or the number, gender, or case of a noun, adjective, or pronoun, without affecting the word's meaning or class (part of speech). Examples of applying inflectional morphemes to words are adding ''-s'' to the root ''dog'' to form ''dogs'', or adding ''-ed'' to ''wait'' to form ''waited''. An inflectional morpheme changes the form of a word. English has eight inflections.


Allomorphs are variants of a morpheme that differ in pronunciation but are semantically identical. For example, the English plural marker ''-(e)s'' of regular nouns can be pronounced (''bats''), , (''bugs''), or , (''buses''), depending on the final sound of the noun's plural form.



A zero-morpheme, is a type of morpheme that carries semantic meaning but is not represented by auditory phonemes. They are often represented by /Ø/ within glosses. Generally, these types of morphemes have no visible changes. For instance, ''sheep'' is both the singular and the plural form. The intended meaning is thus derived from the Co-occurrence determiner (in this case, "some-" or "a-").

Content vs. function

Content morphemes express a concrete meaning or ''content'', and function morphemes have more of a grammatical role. For example, the morphemes ''fast'' and ''sad'' can be considered content morphemes. On the other hand, the suffix ''-ed'' is a function morpheme since it has the grammatical function of indicating past tense. Both categories may seem very clear and intuitive, but the idea behind them is occasionally harder to grasp since they overlap with each other. Examples of ambiguous situations are the preposition ''over'' and the determiner ''your'', which seem to have concrete meanings but are considered function morphemes since their role is to connect ideas grammatically. Here is a general rule to determine the category of a morpheme: * Content morphemes include free morphemes that are nouns, adverbs, adjectives, and verbs, and include bound morphemes that are bound roots and derivational affixes. * Function morphemes may be free morphemes that are prepositions, pronouns, determiners, and conjunctions. Sometimes, they are bound morphemes that are inflectional affixes.

Other features

Roots are composed of only one morpheme, while stems can be composed of more than one morpheme. Any additional affixes are considered morphemes. For example, in the word ''quirkiness'', the root is ''quirk'', but the stem is ''quirky'', which has two morphemes. Moreover, some pairs of affixes have the same phonological form but have a different meaning. For example, the suffix ''–er'' can be either derivative (e.g. ''sell'' ⇒ ''seller'') or inflectional (e.g. ''small'' ⇒ ''smaller''). Such morphemes are called homophonous. Some words might seem to be composed of multiple morphemes but are not. Therefore, not only form but also meaning must be considered when identifying morphemes. For example, the word ''relate'' might seem to be composed of two morphemes, ''re-'' (prefix) and the word ''late'', but it is not. Those morphemes have no relationship with the definitions relevant to the word like "to feel sympathy," "to narrate," or "to be connected by blood or marriage." Furthermore, the length of a word does not determine whether or not it has multiple morphemes. The word ''Madagascar'' is long and might seem to have morphemes like ''mad'', ''gas'', and ''car'', but it does not. Conversely, some short words have multiple morphemes (e.g. ''dogs'' = ''dog'' + ''s'').

Morphological icons

Morphological icons are images, patterns or symbols that relate to a specific morpheme. For children with dyslexia, it has been shown to be an effective way of building up a word. The word 'inviting' as an example is made up of two commonly used morphemes, 'in-' and '-ing'. A morphological icon for 'in-' could be an arrow going into a cup, and '-ing' could be an arrow going forward to symbolise that something is in action (as in ''being, running, fishing''). The concept of combining visual aid icons with morpheme teaching methods was pioneered from the mid 1980s by Neville Brown. He founded the Maple Hayes school for dyslexia in 1981, where he later improved the method alongside his son, Daryl Brown. The school's curriculum uses morphological icons as a learning aid.

Morphological analysis

In natural language processing for Japanese, Chinese, and other languages, morphological analysis is the process of segmenting a sentence into a row of morphemes. Morphological analysis is closely related to part-of-speech tagging, but word segmentation is required for these languages because word boundaries are not indicated by blank spaces. The purpose of morphological analysis is to determine the minimal units of meaning in a language or morphemes by using comparisons of similar forms: for example, comparing forms such as "She is walking" and "They are walking," rather than comparing either with something completely different like "You are reading." Thus, the forms can be effectively broken down into parts and the different morphemes can be distinguished. Similarly, both meaning and form are equally important for the identification of morphemes. For instance, an agent morpheme is an affix like ''-er'' that transforms a verb into a noun (e.g. ''teach'' → ''teacher''). On the other hand, ''–er'' can also be a comparative morpheme that changes an adjective into another degree of the same adjective (eg.. ''small'' → ''smaller''). Although the form is the same, the meanings are different. Also, the opposite can occur, with the meaning being the same but the form being different.

Changing definitions

In generative grammar, the definition of a morpheme depends heavily on whether syntactic trees have morphemes as leaves or features as leaves. * Direct surface-to-syntax mapping in lexical functional grammar (LFG) – leaves are words * Direct syntax-to-semantics mapping ** Leaves in syntactic trees spell out morphemes: distributed morphology – leaves are morphemes ** Branches in syntactic trees spell out morphemes: radical minimalism and nanosyntax – leaves are "nano-" (small) morpho-syntactic features Given the definition of a morpheme as "the smallest meaningful unit," nanosyntax aims to account for idioms in which an entire syntactic tree often contributes "the smallest meaningful unit." An example idiom is "Don't let the cat out of the bag." Here, the idiom is composed of "let the cat out of the bag." This might be considered a semantic morpheme that is itself composed of many syntactic morphemes. Other cases of the "smallest meaningful unit" being longer than a word include some collocations such as "in view of" and "business intelligence", in which the words together have a specific meaning. The definition of morphemes also plays a significant role in the interfaces of generative grammar in the following theoretical constructs: * Event semantics: the idea that each productive morpheme must have a compositional semantic meaning (a denotation), and if the meaning is there, there must be a morpheme (whether null or overt). * Spell-out: the interface where syntactic/semantic structures are "spelled out" by using words or morphemes with phonological content. This can also be thought of as lexical insertion into the syntactic.

See also


* Alternation (linguistics) * Hybrid word * Morphological parsing * Theoretical linguistics * Word stem * Phoneme * Bound morpheme


* Floating tone * Greek morphemes * Morphophonology


* ''Motif-Index of Folk-Literature'', featuring a comparable concept in folklore studies



External links

Glossary of reading terms

Comprehensive and searchable morpheme reference

by Prof. Mark Lieberman
Pronunciation of the word morpheme
{{Authority control Category:Units of linguistic morphology Category:Learning to read Category:Reading (process)