one-thousandth
Noun
Meaning
one part in a thousand equal parts
Source: WordNetSynonyms
Hypernyms
Examples
Hydrogen ions have a single charge and one-thousandth of a gram of hydrogen ions per 100 grams dry soil gives a measure of one milliequivalent of hydrogen ion.
It is a giant planet with a mass one-thousandth that of the Sun, but two and a half times that of all the other planets in the Solar System combined.