real number


: a number that has no imaginary part
the set of all real numbers comprises the rationals and the irrationals

Word History

First Known Use

circa 1909, in the meaning defined above

Time Traveler
The first known use of real number was circa 1909

Dictionary Entries Near real number

Cite this Entry

“Real number.” Dictionary, Merriam-Webster, Accessed 21 Jul. 2024.

Kids Definition

real number

: a number (as −2, 3, ⅞, .25, 12, π) that is rational or irrational

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