What is this enchant for?

I have the question what or for what item the enchant suction is intended. I play the pe 1.13 version in minecraft

Suction allows the player to fly in the direction of the trident when the trident is thrown under water or in the rain.

For the trident. If you throw the trident then it will pull you in so to speak, so you'll be pulling a few blocks in its direction

Should be the enchantment for the Trident who can be catapulted through the air.
If on a Trident, then you can throw it in the water and rain while you cling to it, try it out, but then you can't use it as a throwing weapon anymore…