This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 氶 is uncertain. It appears as a component in other characters, but its independent origin is not well established.
The shape looks like a hand reaching down to scoop water: the top stroke is the hand, and the bottom is water (水). This can remind you of the kun reading すく.う (to scoop), but the kanji itself has no fixed meaning.
For ショウ, imagine a show where a performer scoops water with a giant hand-shaped prop: show -> ショウ, and the scooping motion matches the shape.