A prediction or educated-guess based on current evidence that is yet to be tested.
I hypothesize that my pants will decend.
It seems that my hypothesis was correct. Now, to get funky.
A guess made by someone with a PhD.
In common usage, the words hypothesis, model, theory, and law have different interpretations and are at times used without precision, but in science they have very exact meanings. A hypothesis is a limited statement regarding the cause and effect in a specific situation, which can be tested by experimentation and observation or by statistical analysis of the probabilities from the data obtained.
It's not just a guess, it's a hypothesis.