Definition of "trillionth" [trillionth]

• The ordinal number matching the number one trillion in a series. (noun)
• One of a trillion equal parts. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Five'Mathematicians Shigeru Kondo and Alexander Yee's big reveal, after building and writing code for a computer that would calculate the 10 trillionth digit of pi."
• "We might be living in the trillionth universe or any of an infinite sequential universes."
• "Remember that Contador tested positive for 50 picograms (a picogram is a trillionth of a gram) of clenbuterol per milliliter of urine."