ancient ballista for throwing heavy stones, cannon, gun
礟 centers on a device that launches projectiles: an ancient stone-throwing ballista, or later a cannon or gun. The core idea is a weapon that hurls heavy objects.
礟 combines 石 (stone) with 駁, which likely contributes a phonetic element. The character is associated with stone-throwing weapons, but its detailed historical development is uncertain.
The stone radical 石 on the left suggests heavy projectiles, while the right side 駁 looks like a complex mechanism. Picture an ancient catapult made of stone and intricate parts, ready to hurl a boulder.
For ホ, imagine the sound of a cannon firing: a deep 'ho' echoing as the stone flies. Ho -> ホ.