玉兎 is read as ぎょくと (gyokuto) and means moon.
ぎょくと
gyokuto
きんうぎょくと
sun and moon
たま
ball (i.e. a testicle)
ぎょくおん
the Emperor's voice
ぎょくさい
trying but being utterly beaten
たまねぎ
onion (Allium cepa)
たまむしいろ
iridescent colour
ぎょくろ
high-quality green tea
たまつき
serial collisions (of cars)
たまがわだいがく
Tamagawa University
ぎょくせいり
liquidation of speculative accounts
たまむすび
thread knot (end of the thread tied up to a knot)
たまいれ
tama-ire