From thousand + -th.

• IPA: /ˈθaʊzəndtθ/, IPA: /ˈθaʊzəntθ/, IPA: /ˈθaʊzəndð/, IPA: /ˈθaʊzənθ/, IPA: /ˈθaʊzənð/

thousandth (not comparable)

1. The ordinal numeral form of one thousand; last in order of a series of a thousand; next after the nine hundred and ninety-ninth.

• French: millième
• German: tausendste
• Italian: millesimo
• Portuguese: milésimo
• Russian: ты́сячный
• Spanish: milésimo

thousandth (plural thousandths)

1. (singular only) The person or thing in the thousandth position.
2. One of a thousand equal parts of a whole.
   • 1891, Oscar Wilde, chapter XIV, in The Picture of Dorian Gray, London, New York, N.Y., Melbourne, Vic.: Ward Lock & Co., →OCLC ↗, page 256 ↗:

     “Ah, Alan,” murmured Dorian, with a sigh, “I wish you had a thousandth part of the pity for me that I have for you.”

• French: millième
• German: Tausendste
• Italian: millesimo, millesima
• Portuguese: milésimo, milésima
• Russian: ты́сячный
• Spanish: milésimo, milésima

• French: millième
• German: Tausendstel
• Italian: millesimo
• Portuguese: milésimo
• Russian: одна тысячная
• Spanish: milésimo