gush forth
濆 centers on water bursting out forcefully: gushing or spurting forth. The single given meaning is a vivid, specific action of liquid erupting.
濆 combines 氵 (water) with 賁, which likely contributes the sound and carries a sense of bursting or rushing. The character is not common in modern Japanese, and its detailed historical development is uncertain.
Water 氵 on the left and 賁 on the right: picture a decorative fountain (賁 can suggest ornamentation) where water gushes forth forcefully.
For フン, imagine a fun water park where jets of water gush forth: fun -> フン, and the water erupts all around you.