Cautious with Ray drunk (4)
I believe the answer is:
wary
'cautious' is the definition.
('wary' can be similar in meaning to 'cautious')
'with ray drunk' is the wordplay.
'with' becomes 'w' (abbreviation).
'drunk' indicates anagramming the letters.
'ray' with letters rearranged gives 'ary'.
'w'+'ary'='WARY'
(Other definitions for wary that I've seen before include "Cautious and vigilant.17 Add up for infant" , "Cautious, suspicious" , "Distrustful" , "James Bond villain" , "Displaying caution" .)