Could you credit a sailor catching one? (4)
I believe the answer is:
crab
'could you' is the definition.
I can't tell whether this defines the answer.
'credit a sailor catching one?' is the wordplay.
'credit' becomes 'cr'.
'a sailor' becomes 'b' (I can't explain this - if you can you should give a lot more credence to this answer).
'catching' indicates putting letters inside.
'one?' becomes 'a'.
'cr'+'b'='crb'
'crb' placed around 'a' is 'CRAB'.
Can you help me to learn more?
(Other definitions for crab that I've seen before include "Shellfish with pincers" , "one is a fiddler" , "Seashore creature" , "Crustacean with pincers - grumble" , "Decapod crustacean" .)