1. a rate or proportion expressed in parts per thousand
Usage: technical

Examples

• The permillage of salt in seawater is approximately 35.
• Blood alcohol content is sometimes measured in permillage rather than percentage.
• The engineer calculated the permillage of impurities in the metal alloy.
• Environmental scientists use permillage to express trace pollutant concentrations.
• The permillage system allows for more precise measurements than percentages.
• Industrial quality control often relies on permillage calculations.