the moon like the rhine moves northward

Splash is a nice word but plash, which means the same thing, is even nicer. I suppose it’s because there’s no initial /s/ to detract from the pla with that long /a/ and the pl of plush, plop and pleasure.

Both words require liquid so maybe it’s the kind of liquid or its consistency that determines if it’s to be splash or plash. Like is it mud or is it ocean or is it 7Up? Or maybe it’s the agent entering the liquid that decides, although strictly speaking an agent may not be necessary. Bubbling hot oil, after all, splashes up like a goddamn. (And this is not a case for splatter, which needs an object. A new white blouse is good.)

Most dictionaries don't differentiate but some suggest it is a matter of degree separating plash from splash. To my ear it sounds that way, plash being a damped-down version of splash. People should use plash more often, helping to prove that -

1. All bath beads dropping into water plash.
2. Cream being agitated with a churn to make butter splashes.
3. Wooden spoons whacking the surface of a thick, simmering pudding plashes.
4. Suicides jumping from bridges into rivers splash.
5. Children playing in a pool plash, until things get out of hand, when they splash.