Argus-eyed
aware
cognisant
cognizant
energetic
fly
heads-up
lidless
open-eyed
sleepless
vigilant
wakeful
wide-awake
Klaxon
Mayday
SOS
active
admonish
advertent
advise
agile
agog
air-raid alarm
alarm
alarm bell
alarm clock
alarm signal
alarum
alert for
alive
all clear
all ears
all eyes
animated
apt
arouse
assiduous
attentive
awake
beacon
blinking light
brainy
breathe
bright
brilliant
brisk
burglar alarm
buzz
buzzer
cant
careful
caution
cautious
clear-sighted
clear-witted
clearheaded
clever
concentrated
confide
confide to
alerted
alerting
alertness
alerts
able
confident
eager
intelligent
keen
shrewd
watchful
Bert
Curt
Evert
Insert
Kurt
assert
avert
birt
blurt
burt
chert
concert
convert
curt
desert
dessert
dirt
disconcert
divert
evert
exert
flirt
gert
girt
hert
hurt
inert
insert
invert
overt
peart
pert
pervert
reassert
revert
shirt
skirt
spurt
squirt
subvert
turret
unhurt
vert
wert