A Wave is symbolized as one of the strongest forces on earth (Strength). also if you read more into it, its about faith, a wave is you against mother nature, you cannot control it, you just have to put your faith into her.
Just a thought. As a part of deathly gallows symbol, I could have this in the centre as the wand by extend further past it? Browse through over high quality unique tattoo designs from the world's best tattoo artists!