radical sign
noun Mathematics.
the symbol √ or 
indicating extraction of a root of the quantity that follows it, as √25=5 or 
.
indicating extraction of a root of the quantity that follows it, as √25=5 or .Nearby words
radical expression, radical hysterectomy, radical left, radical mastectomy, radical right, radical sign, radicalism, radicalize, radically, radicand, radicant
Origin of radical sign
First recorded in 1660–70
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for radical sign
radical sign
noun
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
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