major planet

Short definition from Wiktionary

Noun

1. 1
   Any of the 8 celestial bodies which orbit the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune (a celestial body that fits the 2006 IAU definition of planet).
2. 2
   Any planet that is significantly larger and more massive than Earth, containing large amounts of hydrogen and helium, such as Jupiter and Neptune.