|This article relies largely or entirely upon a single source. (August 2013)|
A closely related concept is that of an analytic language, which uses little or no inflection to indicate grammatical relationships. Isolating and analytic languages tend to coincide and are often identified. However, an analytic language may still contain polymorphemic words due to the presence of derivational morphemes.
Isolating languages contrast with synthetic languages, where words often consist of multiple morphemes. That linguistic classification is subdivided into the classifications fusional, agglutinative, and polysynthetic, which are based on how the morphemes are combined.
Although historically languages were divided into three basic types (isolating, flectional, agglutinative), these traditional morphological types can be categorized by two distinct parameters:
- morpheme per word ratio (how many morphemes there are per word)
- degree of fusion between morphemes (how separable words' inflectional morphemes are according to units of meaning represented)
A language is said to be more isolating than another if it has a lower morpheme per word ratio.
To illustrate the relationship between words and morphemes, the English term "rice" is a single word consisting of only one morpheme (rice). This word has a 1:1 morpheme per word ratio. In contrast, "handshakes", is a single word consisting of three morphemes (hand, shake, -s). This word has a 3:1 morpheme per word ratio. On average, words in English have a morpheme per word ratio substantially greater than one.
If English were an isolating language, "handshakes" might be rendered as "shake of hand s", with each morpheme forming a separate word.
It is perfectly possible for a language to have one inflectional morpheme yet more than one unit of meaning. For example, the Russian word vídyat/видят 'they see' has a morpheme per word ratio of 2:1, having two morphemes: the root vid-/вид-, which conveys the imperfective aspect meaning, and the inflectional morpheme -yat/-ят which inflects for three units of meaning (3rd person subject, plural subject, present/future tense). Effectively, four units of meaning in one inseparable morpheme: -yat/-ят.
Languages that are relatively more isolating have a morpheme per word ratio that approaches 1:1. A purely isolating language would lack any visible morphology, since no word would have an internal compositional structure in terms of word pieces (i.e. morphemes) – thus it would lack bound morphemes like affixes.
The morpheme per word ratio is a scalar category ranging from low ratios (approaching 1:1) on the isolating hypothetical pole of the scale, to a high morpheme per word ratio. The greater the overall ratio, the less isolating and the more synthetic the language.
- Whaley, Lindsay J. (1997). "Chapter 7: Morphemes". Introduction to Typology: The Unity and Diversity of Language. SAGE Publications, Inc.
- Sapir, Edward (1921). Chapter 6: "Types of linguistic structure". In Language: An Introduction to the Study of Speech.