Back formation

In etymology, back-formation is the process of creating a new lexeme by removing actual or supposed affixes. The resulting neologism is called a back-formation, a term coined by James Murray in 1889. (OED online preserves their first use of 'back formation' from 1889 in the definition of to burgle.)

For example, the noun resurrection was borrowed from Latin, and the verb resurrect was then backformed hundreds of years later from it by removing the ion suffix. This segmentation of resurrection into resurrect + ion was possible because English had examples of Latinate words in the form of verb and verb+-ion pairs, such as opine/opinion. These became the pattern for many more such pairs, where a verb derived from a Latin supine stem and a noun ending in ion entered the language together, such as insert/insertion, project/projection, etc.

Back-formation may be similar to the reanalyses or folk etymologies when it rests on an erroneous understanding of the morphology of the longer word. For example, the singular noun asset is a back-formation from the plural assets. However, assets is originally not a plural; it is a loanword from Anglo-Norman asetz (modern French assez). The -s was reanalyzed as a plural suffix.

Back-formation is different from clipping – back-formation may change the word's class or meaning, whereas clipping creates shortened words from longer words, but does not change class or meaning of the word.

Words can sometimes acquire new lexical categories without any derivational change in form (for example, ship was first a noun and later was used as a verb). That process is called conversion (or zero-derivation). Like back-formation, it can produce a new noun or a new verb, but it involves no back-forming.

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