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noun Linguistics.

1. the analogical creation of one word from another word that appears to be a derived or inflected form of the first by dropping the apparent affix or by modification.
2. a word so formed, as typewrite from typewriter.

noun

1. the invention of a new word on the assumption that a familiar word is derived from it. The verbs edit and burgle were so created from editor and burglar
2. a word formed by this process