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radical sign

American  

noun

Mathematics.
  1. the symbol √ or indicating extraction of a root of the quantity that follows it, as √25=5 or .


radical sign British  

noun

  1. the symbol √ placed before a number or quantity to indicate the extraction of a root, esp a square root. The value of a higher root is indicated by a raised digit in front of the symbol, as in ³√

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of radical sign

First recorded in 1660–70

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Transformation of radicals Fraction under the radical sign.Reduction to an entire surd.Changing to surds of different order.Reduction to simplest form.

From Project Gutenberg

There are certain "radical signs" and a number of "primitive" signs; characters are made by combining both, and are written downwards.

From Project Gutenberg