My daughter threw a vase at my head and gave me a serious injury that needed seven stitches.
On the Setsubun, we threw dried beans at Koichi and chased the evil spirits away.
"Salmon, I’m mad about you." "Fugu, I’m actually mad at you! Why did you throw garlic at me? "S..sorry I’ve heard that salmon like the smell of garlic."
You know that you're throwing something that is attaching to something else. How else can you say that? The best way would be to say to throw against or to throw at.
The readings just come from two vocab words you've hopefully seen already: 投げる and 付ける. So long as you know the readings for those words, the reading for this word should be no problem for you.