vigilant
/ˈvɪdʒɪlənt/adjective
- keeping careful watch for possible danger or difficulties警惕的; 警戒的：
the burglar was spotted by vigilant neighbours.
窃贼被警惕的邻居发现了。
派生词
vigilantly
adverb词源
late 15th cent.: from Latin vigilant- 'keeping awake'， from the verb vigilare, from vigil （see VIGIL）.