vigilant
adjective
[ ˈvɪdʒɪl(ə)nt ]
• keeping careful watch for possible danger or difficulties.
• "the burglar was spotted by vigilant neighbours"
Similar:
watchful,
on the lookout,
observant,
sharp-eyed,
keen-eyed,
gimlet-eyed,
eagle-eyed,
hawk-eyed,
with eyes like a hawk,
with one's eyes open,
attentive,
paying attention,
alert,
on the alert,
on one's toes,
on the qui vive,
awake,
wide awake,
unsleeping,
on one's guard,
on guard,
concentrating,
careful,
cautious,
wary,
chary,
circumspect,
prudent,
heedful,
mindful,
prepared,
ready,
beady-eyed,
not missing a trick,
on the ball,
leery,
regardful,
Argus-eyed,
Origin:
late 15th century: from Latin vigilant- ‘keeping awake’, from the verb vigilare, from vigil (see vigil).
