trillionth

1 of 2

adjective

tril·​lionth -n(t)th How to pronounce trillionth (audio)
1
: being number one trillion in a countable series see Table of Numbers
2
: being one of a trillion equal parts into which anything is divisible

trillionth

2 of 2

noun

"
plural trillionths
-yən(t)s
-yən(t)ths
1
: number one trillion in a countable series
2
: the quotient of a unit divided by one trillion : one of a trillion equal parts of anything
3
: a minute part

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Cite this Entry

“Trillionth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trillionth. Accessed 22 Dec. 2025.

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