Argus-eyed
upon one's guard
on guard
on your guard
on one's guard
ever-watchful
everwatchful
watch and ward
on watch
vigilantness
wakeful
weather eye
jealousy
watchfulness
vigilance
keep cave
ward
waker
keep a lookout
keep an eye open
supervigilant
open-eyed
vigilantly
wary
look out
watch out
invigilation
watch
keep one's stick on the ice
aware
hypervigilantly
stand guard
argus-eyed
watchful
vigilant
on the alert
cautiousness
watcher
hypervigilant
off his guard
carefulness
off-guard
off her guard
mind out
off one's guard
watchingness
off guard
off your guard
napping
wariness