yin yang Character

陰 yin
陽 yang

阝 or 阜 radical "mound; hill"
with the phonetic indicators yin 侌 and yang 昜.

侌 "cloudy" ideographically combines jin 今 "now; present" and yun 云 "cloud", denoting the "今 presence of 云 clouds".
昜 "bright" originally pictured 日 the "sun" with 勿 "rays coming down".

The "mound; hill" radical 阝full forms semantically specify yin 陰 "shady/dark side of a hill" and yang 陽 "sunny/light side of a hill".

The Simplified Chinese characters 阴 and 阳 for yin and yang combine the same "hill" radical 阝 with the non-phonetic yue 月 "moon" and ri 日 "sun", graphically denoting "shady side of a hill" and "sunny side of a hill".

Compare the Classical Chinese names (which contain tai 太 "great") for these two heavenly bodies: Taiyin 太陰 "moon" and Taiyang 太陽 "sun".

https://en.wikipedia.org/wiki/Yin_and_yang

左 zuǒ left
右 yòu right (-hand)