(damn right it's plural. that's how they're sold. you can't buy one
snowball)
hostess product, consisting of a hemisphere of hostess standard chocolate cake and cream filling, 3/8" of rubbery marshmallow-ish stuff, and colored coconut. Sometimes you can get them with uncolored coconut, but they're normally hideous pink. Near holidays, you can get other colors, like green for St. Patrick's day, and yellow, purple, blue for easter.
They're best frozen.