It’s rude to interrupt a person.
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 intercept, so the verb version is to intercept or to interrupt.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You haven't learned this reading yet, so here's a mnemonic to help you:
The thing you want to interrupt and to intercept is your roommate's sighing guitar (さえぎ). He keeps playing it and all it does is make these horrible, long sighing sounds. You want to interrupt it any cost.