Dripwave is an art style/genre of music/culture that is centered around water sounds and imagery. "Drip" sounds are a big part of the music, and may be modified in many different ways.
Somebody who is stupid or annoying. Most likely came from the usage of "dip" a tobacco product that's usage involves dipping ones lip into a pile of it. The meaning of dipwad is literally a wad of dip, created by ones saliva, which is quite an unpleasant thing.