This is the 5093rd most frequent Polish word.
promile
"Promile" in Polish means "per mille" or "parts per thousand."
Here, 'promile' is used to refer to the concentration of alcohol in someone's breath in terms of 'per mille', a unit of measurement of substance amount.
W wydychanym powietrzu miał dwa promile alkoholu.
In his breath, he had two per mille of alcohol.
In this sentence, 'promile' refers to a fraction of the total value, indicating the tax rate in 'per mille'.
Podatek od sprzedaży wynosi dwa promile całkowitej wartości.
The tax on sales is two per mille of the total value.
Here, 'promile' is used to quantify salinity as 'parts per thousand', providing a measure of salt concentration.