• 玉たま — ball; sphere; bullet
• 目玉めだま — eyeball; main attraction
• 玉ねぎたまねぎ — onion
• 玉座ぎょくざ — throne
• 玉川たまがわ — Tamagawa (place name)

“玉” can mean a literal ball or sphere, and it also carries a “precious” nuance in words related to gems or jade. In everyday Japanese, it also appears in familiar words like 玉ねぎ (onion) and 目玉 (eyeball / main attraction).