"Fugu, you don’t understand why Salmon is mad at you, do you?" "No, I have no idea." "That’s what I thought."
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means angry, the verb vocab version is to get angry.
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're starting to get angry about something. It's mostly this okra (おこ). It tastes terrible.