Well, you already got the definition according to what's accepted within the Leopard Gecko Community, but I'll give you the true genetic definition of what a "Hypo" and "Super Hypo" are.
"Hypo" is short for hypomelanistic. Hypomelanistic means that the animal has a reduced amount of black pigment(melanin)to varying degrees. Now I'm not too familiar with Leopard gecko morphs, but by saying "Super Hypo" most would take it as saying that this is a Co-Dominant trait (hets are visibly intermediate between a "Normal" and the "Super/Homozygous" form). If this is in fact the case with the "Hypo" morph in Leopards then you're animal should be showing a slightly reduced amount of black if it is a het/hypo, and little to none if it is indeed a super.
The only true way to prove whether or not the animal is a super, is 1) to breed the animal to a normal, if you produce 100% hypos, then it is a "Super", if it produces roughly 50%, then it is a "het/hypo". 2) if you know that the animal came from a Super X normal clutch, then it would definitely be a "Het/Hypo", or if you knew it came from a Super X Super clutch, then it would be a "Super" positively.
These are the only ways to determine 100% what the genetics of the animal are, but like it was said above, there are clues that can allow you to make a edumacated guess (pun intended).
-Dan