drum
鼖 centers on a large drum, specifically a type of drum used in ancient contexts. The meaning is straightforward and concrete.
鼖 combines 卉 (plants) on top with 鼓 (drum) on the bottom. The exact historical development is uncertain, but it likely represents a type of drum associated with ceremonial or military use, possibly decorated with plant motifs.
Picture a large drum (鼓) adorned with plants (卉) on top, like a ceremonial drum used in ancient festivals. The plants decorate the drum, making it a special drum.
For フン, imagine the fun sound of a big drum booming: fun -> フン, and the drum's deep tone fills the air.