The term 'moon of Neptune' refers to the five moons that orbit the planet Neptune. These moons are TRITON (6 letters), NEREID (6 letters), Galatea (7 letters), Despina (7 letters), and Larissa (7 letters). TRITON is the largest of the five moons and is the only one with a retrograde orbit, meaning it orbits in the opposite direction of Neptune's rotation. NEREID is the second-largest moon and has an eccentric orbit, meaning its distance from Neptune varies over time. Galatea, Despina, and Larissa are much smaller than TRITON and NEREID and have prograde orbits, meaning they orbit in the same direction as Neptune's rotation. All five moons are believed to have been formed from the same collision that created Neptune's rings.