I wouldn't say "波紋 / hamon" is the name of a martial art. If anything, I think that would be "仙道 / sendô", which is admittedly a bit tricky to translate (I seem to remember I went with the Chinese equivalent when I translated that part... Sanskrit would be nice though).
Yeah, ripple refers to the source of the power, and the nature of it. I think it would be a mistake to give it anything with additional flavor because it is basically just the explanation for the power.