The description of the word you requested from the astronomical dictionary is given below.
Jupiter = [Latin] chief god
Jupiter is the fifth planet of the Solar System, counting from the Sun. Jupiter is a jovian planet, with a very dense and thick atmosphere (of mostly hydrogen and helium), many moons, and narrow rings. Jupiter is the largest and most massive planet in our Solar System. Jupiter has an equatorial diameter of 142,984 km and is number 2 on the list of largest objects in our Solar System.