faint-hearted

柯林斯词典

1. ADJ If you describe someone or their behaviour as faint-hearted, you mean that they are not very confident and do not take strong action because they are afraid of failing. 胆怯的; 懦弱的
This is no time to be faint-hearted. 现在不是胆怯的时候。
2. PHRASE If you say that something is not for the faint-hearted, you mean that it is an extreme or very unusual example of its kind, and is not suitable for people who like only safe and familiar things. 胆小者(不适)[usu v-link PHR]
It's a film about a serial killer and not for the faint-hearted. 这是部关于连环杀手的电影，胆小者勿近。