Anxious or afraid (8)
I believe the answer is:
insecure
This clue is a double definition.
'anxious' is the first definition.
(similar in meaning)
'afraid' is the second definition.
(similar in meaning)
(Other definitions for insecure that I've seen before include "safe? Hardly" , "open to attack" , "Loose" , "Defenceless" , "Anxious - feeling unsupported" .)