Iteration mark

Iteration marks are characters or punctuation marks that represent a duplicated character or word.

In Chinese, 二 (usually appearing as 〻) or 々 is used in casual writing to represent a doubled character, but it is never used in formal writing or printed matter. In a tabulated table or list, vertical repetition can be represented by a ditto mark (〃).

Iteration marks have been occasionally used for more than two thousand years in China. The bronze script from the Zhou Dynasty, shown right, ends with “子_二孫_二寶用”, where the small 二 (“two”) is used as iteration marks in the phrase “子子孫孫寶用” ("descendants to use and to treasure").

In both Indonesian and Malay nouns that are repeated to form plurals can be shortened with the use of "2" e.g. kata (English word) becomes kata-kata (English words) which can be shortened to kata2. Its usage dates back to the time when the languages were written in Jawi, using the Arabic numeral "٢" (e.g. رام٢, butterfly). The usage of "2" can also replaced with superscript version of the same number "²" (e.g. kata² for kata2). Even though its usage is common in handwriting, it is considered to be slang and is not found in formal writing and documents. The use of "2" and "²" has increased in recent years and is no longer limited to pluralization. For example, the Malay word "harap²", shortened from "harap-harap" (literally hopefully), is the emphasized version of "harap" (literally hope). Some youths use "2" and "²" for some changing sound words. e.g. "hingar²" for "hingar-bingar" (English loud); this differs from the original use of the mark for exact duplicates. Apart from the "2" and "²" marks, the ditto mark (″) was also used in Malay and Indonesian to represent a word repeated from the equivalent position in the line above it.

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