This is the noun form of disaster, so it means disaster or misfortune.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
When a disaster strikes, you start moaning and groaning. Say it along with me: "Wahhhhh! Zaahhhh! Waahhhh!" (わざわ). Be careful of the い on the end, it can be tricky and make you think it's an adjective when it's a noun.
This is a lucky charm that protects you from misfortune.
I believed in the phrase, "turn disaster into advantage," and it really worked.
It seems like Shark wishes misfortune upon other people.