square root

plural square roots

1. mathematicsThe number which, when squared, yields the original number.

   Near-synonym: √

   2 more examples

   The square roots of 4 are 2 and −2, the square root of 0 is 0, and the square roots of −4 are 2i and −2i.

   In √a̅+̅b̅, the horizontal bar or vinculum is actually a parenthesis that groups a+b. Without it, √a+b might mean b+√a̅ or it might mean √a̅+̅b̅. Nevertheless, the square-root sign without the vinculum is often used[…].

   a. 1992, Frederick Mosteller, “Writing about Numbers”, in John C. Bailar III, Frederick Mosteller, editors, Medical Uses of Statistics, second edition, published 1992, page 388

   Synonyms: sqr, sqrt, mul:√ · Antonyms: square

2. mathematicsThe positive number which, when squared, yields another number: the principal square root.

   The square root of 4 is 2. No negative real square roots exist. Negative numbers have no real square roots.