per mill

or per mil

[ pur mil, per ]

adverb

1. per thousand.

per mill

/ pə ˈmɪl /

adverb

1. by the thousand or in each thousand

Word History and Origins

Origin of per mill¹

First recorded in 1900–05

Word History and Origins

Origin of per mill¹

C19: from per + French or Latin mille thousand, on the model of per cent