Arnold Zwicky's Blog

In talking about the and/zero alternation in year names (“two thousand and ten” versus “two thousand ten”), I quoted this comment proscribing the and:

That there’s no “and” should be obvious. “And” is only used in numbers when a decimal is involved.

I suggested that the noun “decimal” here should be replaced by “fraction”, on the grounds that numerical expressions involving fractions other than decimal fractions — 2 1/2, for instance — also require an and.

My amendment was predicated on the understanding that “decimal” in the comment above meant ‘decimal fraction’, a meaning that according to OED2 has been attested since 1651. This is a conversion by truncation — the adjective decimal converted to a noun by truncating the phrase decimal fraction.

But then a comment by michael on my “bald assertion” posting led me to entertain another possibility:

my understanding of mackenzie’s comment is she was referring to the pattern, taught by some teachers (including mine), that the ‘and’ stands for the decimal in numbers such as “12.2″ which would be pronounced ‘twelve and two tenths.”

This appears to have decimal meaning ‘decimal point’ — another conversion by truncation, but one that has not yet made it into the OED. Ned Deily tells me that decimal is used this way in air traffic control: where American controllers use point (“three point one four” for 3.14), others use the more easily perceived decimal (“three decimal one four”).

(The generalization about and would still require amendment, since it applies to expressions that have fractions in them but lack decimal points.)

I’ll take up some other details, in particular the schoolteacher hypothesis that and stands for a decimal point, in another posting.

This entry was posted on January 10, 2010 at 8:08 am and is filed under Conversion, Variation. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.