Alert, vigilant (7)
I believe the answer is:
wakeful
I believe this is a double definition.
'alert' is the first definition.
(I've seen this before)
'vigilant' is the second definition.
(I know that vigilant can be written as wakeful)
(Other definitions for wakeful that I've seen before include "Not sleepy" , "Alert, vigilant" , "Not getting off" , "Unable to sleep" .)