per mill

American  

[pur mil, per] / ˌpɜr ˈmɪl, pər /

Or per mil

adverb

1. per thousand.

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per mill British  

/ pə ˈmɪl /

adverb

1. by the thousand or in each thousand

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Etymology

Origin of per mill

First recorded in 1900–05

Example Sentences

The officer involved has been placed on paid administrative leave, per Mill Creek police policy.

From Seattle Times

We get in the tablets, the tablets we obviously can’t give to the gecko because that would be a huge overdose, so we crush the tablets up, we mix it into a suspension, and now the suspension has a set amount of mix per mill and we take the gecko’s weight and we take our desired dosage and then we divide it by the concentration and we have the amount we’re going to give the gecko.

From Slate