n. 计算, 命数法, 数字的读法

Numeration \Nu`mer*a"tion\, n. [L. numeratio a counting out: cf.
F. num['e]ration.]
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. The act or art of reading numbers when expressed by means
of numerals. The term is almost exclusively applied to the
art of reading numbers written in the scale of tens, by
the Arabic method. --Davies & Peck.

Note: For convenience in reading, numbers are usually
separated by commas into periods of three figures each,
as 1,155,465; in continental Europe, periods are used
for a similar division. According to what is called the
``English'' system, the billion is a million of
millions, a trillion a million of billions, and each
higher denomination is a million times the one
preceding. According to the system of the French and
other Continental nations and also that of the United
States, the billion is a thousand millions, and each
higher denomination is a thousand times the preceding.
[1913 Webster +PJC]