radical sign definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
the sign (√ or ) used before a quantity to indicate that the square root (or a specified root indicated by an imposed index number) is to be extracted: derived from the r in Latin radix, root
radical sign definition by American Heritage Dictionary
- The sign √ placed before a quantity, indicating extraction of the root designated by a raised integer. When extracting a square root, the raised integer is customarily omitted.
- The radical sign together with a horizontal bar extending from its top to the end of the expression from which a root is to be extracted.