The meaning of life, according to Aristotle, is to fulfill a function. What is that function? Being human. Qualitatively, what separates man from other species is his reason and ability to reason. So, in order to fulfill our function, we must reason and be able to reason well.
Why do we do this? The end goal is to become happy.
By fulfilling this function, we will be on the path to achieve what all men want: happiness.
Happiness is a lifetime goal. It's a lifetime process. It won't and cannot be achieved during life (maybe) and so the real pleasure is in the distraction. The journey provides us with an ever-increasing context. As we learn more, we understand more and we can discuss more. It genuinely feels good to be a good thinker.
Plato, I think, also followed this sort of thought. The path to happiness is knowledge.
In short, the meaning of life--as I see it--is to fulfill the function of being human.