Glossary term
parts per thousand
Definition
A unit of measure for one part(s) per thousand. The general acceptance is that parts per thousand should be spelled out in full rather than use the 'ppt' abbreviation, which is usually understood to represent 'parts per trillion'. However, oceanography uses the ppt abbreviation – for example, 34 g of salt in 1000 g of seawater is written as 34 ppt.