The description of the word you requested from the astronomical dictionary is given below.
A moon of 12 km diameter at about 20,901,000 km from the planet Uranus. The gravity at its surface is about 0.0003 times as strong as on Earth. The moon goes once around its planet in about 7.9 years. The moon was discovered in 2001. Also called UXXIV (Uranus twenty-four). Its provisional designation was S/2001 U2.