Morphology is a sub-discipline of linguistics that studies word structure. While words are generally accepted as being the smallest units of syntax, it is clear that in most (if not all) languages, words can be related to other words by rules. For example, English speakers recognize that the words dog, dogs and dog-catcher are closely related. English speakers recognize these relations by virtue of the unconscious linguistic knowledge they have of the rules of word-formation processes in English.
Therefore, these speakers intuit that Dog is to dogs just as cat is to cats, or encyclopædia is to encyclopædias; similarly, dog is to dog-catcher as dish is to dishwasher. The rules apprehended by the speaker in each case reflect specific patterns (or regularities) in the way words are formed from smaller units and how those smaller units interact in speech. In this way, morphology is the branch of linguistics that studies such patterns of word-formation across and within languages, and attempts to explicate formal rules reflective of the knowledge of the speakers of those languages.
Fundamental concepts :
Models of morphology :There are three principal approaches to morphology, which each try to capture the distinctions above in different ways. These are:
Note that while the associations indicated between the concepts in each item in that list is very strong, it is not absolute.
Morphological typology:In the 19th century, philologists devised a now classic classification of languages according to their morphology. According to this typology, some languages are isolating , and have little to no morphology an example is the Chinese language; others are agglutinative, and their words tend to have lots of easily-separable morphemes, for example the Turkish; while others yet are fusional, because their inflectional morphemes are said to be "fused" together, both Latin and Greek are classic examples of fusional languages.
Considering the variability of the world's languages, it becomes clear that this classification is not at all clear-cut, and many languages do not neatly fit any one of these types. However, examined against the light of the three general models of morphology described above, it is also clear that the classification is very much biased towards a morpheme-based conception of morphology. It makes direct use of the notion of morpheme in the definition of agglutinative and fusional languages. It describes the latter as having separate morphemes "fused" together (which often does correspond to the history of the language, but not to its synchronic reality).