new moon, crescent moon
朏 centers on the early visible moon phase: the new moon or crescent moon, when the first sliver of light appears after the dark moon.
朏 combines 月 (moon) with 出 (come out), suggesting the moon coming out or appearing as a crescent. The exact historical development is uncertain, but the component combination fits the meaning well.
The moon 月 is coming out 出 from darkness, showing just a thin crescent. Picture the first sliver of moonlight emerging.
For ヒ, imagine the crescent moon as a tiny, high-pitched 'hee' of light peeking out: hee -> ヒ, like a soft gasp when you spot the new moon.
—