thousandth

1 of 2

adjective

thou·​sandth ˈthau̇zᵊn(t)th How to pronounce thousandth (audio)
1
: being number 1000 in a countable series see Table of Numbers
2
: being one of 1000 equal parts into which anything is divisible

thousandth

2 of 2

noun

"
plural thousandths
-ᵊn(t)s
-ᵊn(t)ths
1
: number 1000 in a countable series
2
: the quotient of a unit divided by 1000 : one of 1000 equal parts of anything

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Cite this Entry

“Thousandth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thousandth. Accessed 17 Dec. 2025.

Kids Definition

thousandth

noun
thou·​sandth
ˈthau̇z-ᵊn(t)th
1
: one of 1000 equal parts of something
2
: the one numbered 1000 in a countable series see number
thousandth adjective

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