No, splash does not mean a chicken is an Easter Egger instead of an Ameraucana.Also, "splash" isn't a recognized plumage variety for the ameraucana breed standard. He would be called an Americana (deceiving hatchery trick name) or a Easter egger not that it matters, but some folks may want to know if breeding
The Ameraucana breed comes in Blue.
Breed two blues together, and you get some black, some blue, and some splash.
Breed the black and splash together, and you get a bunch of blues again.
Or breed blue and splash together, and you get blues and splashes.
All of the blue chicken breeds work this way. The splashes are not a recognized color, but they are just as purebred as their parents, siblings, and offspring that are recognized colors.
So there is no reason for a breeder to avoid Splash. Just don't enter them in a show.
(I do not know whether this specific chick is an Easter Egger or an actual Ameraucana. But the feather color alone is not enough to settle the matter.)