Don't panic! Little boy is unable to sail (8)
I believe the answer is:
becalmed
'unable to sail' is the definition.
I can't tell whether this definition defines the answer.
'don't panic little boy' is the wordplay.
'don't panic' becomes 'be calm' (I've seen this in another clue).
'little boy' becomes 'Ed' (nickname or 'little' form of Edward).
'becalm'+'ed'='BECALMED'
'is' acts as a link.
Can you help me to learn more?
(Other definitions for becalmed that I've seen before include "As a sailing ship without wind" , "Motionless (at sea)" , "In the doldrums" , "still at sea" , "(of sailing ship) unable to move" .)