Productivity (linguistics)

In linguistics, productivity is the degree to which native speakers use a particular grammatical process, especially in word formation. It compares grammatical processes that are in frequent use to less frequently used ones that tend towards lexicalization. Generally the test of productivity concerns identifying which grammatical forms would be used in the coining of new words: these will tend to only be converted to other forms using productive processes.

In standard English, the formation of preterite and past participle forms of verbs by means of ablaut (for example, sing–sang–sung) is no longer considered productive. Newly coined verbs in English overwhelmingly use the 'weak' (regular) ending -ed for the past tense and past participle (for example, spammed, e-mailed). Similarly, the only clearly productive plural ending is -(e)s; it is found on the vast majority of English count nouns and is used to form the plurals of neologisms, such as FAQs and Muggles. The ending -en, on the other hand, is no longer productive, being found only in oxen, children, and the now-rare brethren. Because these old forms can sound incorrect to modern ears, regularization can wear away at them until they are no longer used: brethren has now been replaced with the more regular-sounding brothers except when talking about religious orders. It appears that many strong verbs were completely lost during the transition from Old English to Middle English, possibly because they sounded archaic or were simply no longer truly understood.

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