Let me break it down a bit further for you, cause the agglutination is the really sexy thing about the Hungarian language.
Viszont means 'likewise', 'same to you'.
Lát is 'to see', látás makes it a noun (the seeing), and the suffix -ra usually declares a movement onto something. Think of German "Auf Wiedersehen" if you're familiar.
So, taken together, you'll have something like "Unto seeing each other (again)."