Trillion is the number one followed by 12 zeros.(noun)
An example of a trillion is 1,000,000,000,000.
The definition of trillion is related to or of the number one followed by 12 zeros.(adjective)
An example of trillion used as an adjective is in the phrase "a trillion dollars," which means $1,000,000,000,000.
See trillion in Webster's New World College Dictionary
Origin: Fr < tri-, tri- + (mi)llion
See trillion in American Heritage Dictionary 4
Origin: : tri-, third power (from Latin tri-, tri-)
Origin: + (m)illion, million (from Old French milion; see million).
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