TN meaning in Measurement Unit ?

What is Trillion mean?

A trillion is a number with two distinct definitions:

1,000,000,000,000, i.e. one million million, or 1012 (ten to the twelfth power), as defined on the short scale. This is now the meaning in both American and British English.1,000,000,000,000,000,000, i.e. 1018 (ten to the eighteenth power), as defined on the long scale. This is one million times larger than the short scale trillion. This is the historical meaning in English and the current use in many non-English-speaking countries where trillion and billion 1012 (ten to the twelfth power) maintain their long scale definitions.

Originally, the United Kingdom used the long scale trillion but since 1974, official UK statistics have used the short scale. Since the 1950s, the short scale has been increasingly used in technical writing and journalism, although the long scale definition still has some limited usage.

American English has always used the short scale definition.

Other countries use the word trillion (or words cognate to it) to denote either the long scale or short scale trillion. For details, see Long and short scales#Current usage.

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