radical sign

American  

noun

Mathematics.

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

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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√

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Etymology

Origin of radical sign

First recorded in 1660–70

Example Sentences

We use a radical sign, and write, m, which denotes the positive square root of m.

From Textbooks • May 6, 2020

When we use a radical sign, it indicates the principal or positive root.

From Textbooks • May 6, 2020

We also use the radical sign for the square root of zero.

From Textbooks • Apr. 22, 2020

If we want to find the negative square root of a number, we place a negative in front of the radical sign.

From Textbooks • Apr. 22, 2020

In the quadratic formula, what is the name of the expression under the radical sign and how does it determine the number of and nature of our solutions?

From Textbooks • Feb. 13, 2015