A person who works hard talks of hope but a person who is idle talks of dissatisfaction.
This word consists of kanji with hiragana attached. Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means neglect and lazy, so the verb version is to neglect or to be idle.
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:
You decide to neglect everything. Your school, your family, even your own name (なま). You've managed to slack for so long that you can't even remember your name? That's pretty impressive, actually.