to make a person or an animal so frightened that he, she, or it goes away

Don't make too much noise or you'll scare away the birds. 别弄那么大声音，会把鸟儿吓跑的。

She scared off her attacker by screaming. 她大声叫喊，把袭击她的人吓跑了。

to make someone so worried about doing something that they decide not to do it

If you charge as much as that, you'll scare customers off. 如果你要价那么高，会吓跑顾客的。