[In linguistics](https://www.thoughtco.com/recursion-grammar-1691901), recursion occurs whenever you “double up” (etc) on a certain idea. Like “Great-great-great grandchild” or “re-re-wrote.” Another examples would be “I told a friend, who told a friend, who told a friend, …” Any time you hold the idea of repetition inside repetition, recursion has occurred.
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