Figure on going after sunken ship with prow missing (6)
I believe the answer is:
reckon
'figure' is the definition.
(synonyms)
'on going after sunken ship with prow missing' is the wordplay.
I cannot quite see how this works, but
'on' could be 're' ('on' can be mean 'with reference to') and 're' is found in the answer.
'going' could be 'on' (both can mean functioning or activated) and 'on' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for reckon that I've seen before include "Conker (anag.)" , "Calculate or conclude" , "Estimate - judge" , "what people who count will do" , "Count or calculate" .)