relative density
Noun
Meaning
the ratio of the density of something to the density of a standard
Source: WordNetSynonyms
Hypernyms
Hyponyms
Examples
If the reference material is water then a substance with a relative density (or specific gravity) less than 1 will float in water.
A substance with a relative density greater than 1 will sink.
For example, an ice cube, with a relative density of about 0.91, will float.
For true (in vacuo) relative density calculations air pressure must be considered (see below).
Hydrometer main The relative density of a liquid can be measured using a hydrometer.
If a substance's relative density is less than one then it is less dense than the reference; if greater than 1 then it is denser than the reference.