形容詞 drastic:

1. forceful and extreme and rigorous

1. Our budget needs drastic revision.
   我們的預算需作重大修改。
2. Drastic measures will have to be taken to restore order.
   為恢復秩序必須采取嚴厲措施。

dras.tic

adj.（形容詞）
Severe or radical in nature; extreme:
嚴厲或劇烈的；極端的：
例句：
the drastic measure of amputating the entire leg; drastic social change brought about by the French Revolution.
截除整條腿的極端措施；法國革命帶來的劇烈的社會變動

Taking effect violently or rapidly:
作用迅速而猛烈的：
例句：
a drastic emetic.
烈性的催化藥

來源：
Greek drastikos [active]
希臘語 drastikos [活躍的]
from drastos [to be done]
源自 drastos [被做]
from dran [to do]
源自 dran [做]

【引伸】
dras.tically
adv.（副詞）