玉
たま · tama · JLPT N3 · noun
ball
🔮🪙 Sounds like tomato, which is a round red ball
玉 started as a string of jade beads, and the dot is what separates it from 王 (king). Anything small and round can be a tama: 百円玉 is a 100-yen coin, and 目玉 (eye + ball) is an eyeball.
玉 — three horizontal jades 三 strung on a vertical cord 丨, with a dot added
Originally a pictograph showing three flat jade discs threaded together on a string, the character meant 'jade' or precious stone. A dot was later added to distinguish it from 王 ('king'), which had nearly the same shape. It now refers to jade and, by extension, anything precious or beautiful.