Astronomical term for a giant planet composed mainly of elements heavier than hydrogen and helium, such as oxygen, carbon, nitrogen, and sulfur. Uranus and Neptune are the ice giants in our solar system. Often contrasted with gas giants (木星型惑星).
See also: 天王星型惑星
Uranus and Neptune are classified as ice giants.
巨大氷惑星の内部構造はガス惑星とは異なる。
The internal structure of ice giants differs from that of gas giants.
Compound of 巨大 (きょだい, 'giant'), 氷 (ひょう, 'ice'), and 惑星 (わくせい, 'planet'). Calque of English 'ice giant'.