: per thousand

permillage

2 of 2

noun

plural -s
: rate or proportion per thousand

Word History

Etymology

Adverb

per + Latin mille thousand

Noun

per mill + -age

First Known Use

Adverb

1682, in the meaning defined above

Time Traveler
The first known use of per mill was in 1682

Browse Nearby Words

Cite this Entry

“Per mill.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/per%20mill. Accessed 1 Aug. 2026.

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