gas giant

A gas giant is a giant planet such as Jupiter or Saturn: massive and mostly gas, i.e., hydrogen and helium. Many discovered extra-solar planets are gas giants which is to be expected because larger planets are easier to detect.

The term gas giant is also used for the giant planets Uranus and Neptune, but the distinct term ice giant is also often used for them: they differ from Jupiter and Saturn, one of their differences being inclusion of a substantial amount of frozen volatiles.