A cranberry word, in linguistics and morphology, is an exceptional compound word that is stored in the lexicon (or 'mental dictionary') in its full form, rather than being built from productive rules of grammar. The typical example is cranberry, which, unlike teapot, could not have been formed from a combination of two words, since *cran is not a word. Sometimes cranberry words are referred to as fossilised terms or cranberry morphemes.
Languages often form new words by combining existing words. Because speakers can always come up with new, acceptable words, this process appears to be a consequence of a rule within the minds of the users of the language. For example, in English, a rule allows for the formation of words such as schoolboy and teapot. Of two words, one can be assigned headedness (i.e. is more important); in English, most compounds are endocentric, or headed in this way. Speakers will judge that pot in teapot is the head; in English the head is usually rightmost. The head will take inflections such as plural -s. The remaining part of the compound (e.g. tea) modifies the head, so in this case the compound describes a kind of pot, not a kind of tea.
This procedure is 'productive', meaning that speakers can use the rule to create new words. With cranberry words, this procedure is blocked. Although such words can be analysed as two units, one is either not a word in its own right, or means something different. Therefore, they could not have been formed from kind of rules set out above. A more likely interpretation is that they stand alone as lexical exceptions.
Some words appear to be derived from a productive rule, but cannot be divided into two units that are indisputably related to the compound. For example, blackberry appears to be formed from the adjective black and the noun berry, yet not all berries that are black are blackberries. Looking at other berries, the word gooseberry seems involve a word that in isolation most often refers to a bird. Since the goose- of gooseberry is not the same goose as an avian goose, there is no justification for treating them as the same word stored in the mind's lexicon; more likely, gooseberry is not a compound, but a word in its own right.
- Anderson SR (1990) 'A-morphous morphology'. Manuscript, Cognitive Science Center. Baltimore: John Hopkins University.
- Katamba F & Stonham J (2006) Morphology. Basingstoke: Palgrave. 2nd edition. ISBN 1403916440.
- Katamba & Stonham (2006: 316-336).
- Anderson (1990).
- Katamba & Stonham (2006: 334-336).