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re·cur·sion (rĭ-kûrzhən)
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n.
1. Mathematics
a. A method of defining a sequence of objects, such as an expression, function, or set, where some number of initial objects are given and each successive object is defined in terms of the preceding objects. The Fibonacci sequence is defined by recursion.
b. A set of objects so defined.
c. A rule describing the relation between an object in a recursive sequence in terms of the preceding objects.
2. Linguistics The property of languages in which a structure, such as a phrase or clause, may form a part of a larger structure of the same kind, allowing for a potentially infinite variety of constructions.

[Late Latin recursiō, recursiōn-, a running back, from Latin recursus, past participle of recurrere, to run back; see RECUR.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.