name of a star
婺 is a rare kanji whose core meaning is the name of a star. Its standalone meaning is narrow and does not extend to general concepts.
婺 combines 敄 (possibly phonetic) with 女 (woman), but the exact historical origin as a star name is uncertain.
The top 敄 looks like a spear 矛 with a hand 攵, and the bottom 女 is a woman. Picture a woman holding a spear under the stars, naming a specific star after her.
For ブ, imagine a star named Boo: Boo -> ブ, and the woman under the stars points up at it.
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