syllable
砵 is a rare kanji used phonetically to represent the syllable 'ou' or 'hatsu', with no clear standalone meaning. Its meaning is uncertain.
砵 is a modern Japanese kokuji or phonetic borrowing, combining 石 (stone) with 本 (origin/book) for sound representation. The exact historical development is uncertain.
砵 has no clear meaning, but visually it looks like a stone (石) next to a book (本). Imagine a stone tablet with a single syllable carved into it.
For オウ, picture a stone tablet with the syllable 'ou' carved into it, like a mysterious ancient sound. The stone (石) and book (本) together hold the sound 'ou'.
—