a. and sb. [f. prec. + -TH.] a. adj. The ordinal adjective corresponding to ‘trillion.’ b. sb. One part out of a trillion.
1742. J. Marsh, Decimal Arithmetic Made Perfect, 88. The approximate Product is defective of being the true Product in the Quantity 821947003/998999001 of One, one trillionth Part of an Unit, the Value of the Fraction left out.
1817. Sir J. Leslie, Philosophy of Arithmetic, 132. The accuracy now pursued for the sake of exemplification, is indeed superfluous, approaching within a trillionth part of the truth.
1848. Fraser’s Mag., XXXVII. 647. The millionth of a grain is a common dose; and a trillionth, octillionth, even a decillionth, very usual ones.
1851. Ruskin, Sheepfolds, 16. The seven-millionth or trillionth of its collective evidence.
