Nū'mer-ā'tion, n.

n. [Lat. numeratio, Fr. numération, Pr. numeracio, Sp. numeracion, It. numerazione.] 1. The act or art of numbering. Numeration is but still the adding of one unit more, and giving to the whole a new name or sign. Locke. 2. (Arith.) The act or art of dividing off a series of figures according to their values, and expressing them in words; the act or art of reading numbers, especially as written in the scale of ten, by the Arabic method. Math. Dict. “Our present numerative system is stated by writers to employ the words unit, ten, hundred, thousand, million, billion, trillion, quadrillion, quintillion, sextillion, septillion, octillion, nonillion, &c. But the greater part of this is pure statement; for the terms billion, trillion, &c., though defined by arithmetical writers, have never found their way into common use, the want of such large numbers having never been experienced. Tonstal expressly says that, in his time (Henry VIII.), the common reckoning from millions was made by millions of millions, &c., and . . . Recorde uses nothing more than millions repeated; so that it seems the billions and higher denominations were never any thing but a fancy of arithmetical writers. The probability of this is increased by their meaning different things in different countries; with us [i. e., in England], the billion is a million of millions, a trillion a million of billions, and each denomination is a million times the one preceding. With the French and the other Continental nations (except some of the older writers, at least among the Italians) [and also in the United States], the billion is a thousand millions, and each denomination is a thousand times the preceding.” Eng. Cyc.