Ray of light shows doctor at ships widest point (8)
I believe the answer is:
moonbeam
'ray' is the definition.
(I know that moonbeam is a type of ray)
'of light shows doctor at ships widest point' is the wordplay.
I cannot quite see how this works, but
'of' could be 'o' and 'o' is found in the answer.
'light' could be 'beam' (beam is a kind of light) and 'beam' is present in the answer.
'doctor' could be 'mo' (medical officer) and 'mo' is found within the answer.
'point' could be 'n' (N is an example) and 'n' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for moonbeam that I've seen before include "Lunar shaft of light" , "reflective illumination" , "Ray, not the brightest" , "Night shiner" , "Pale ray of light" .)