He'll be promoted if he's able, and vice versa (8,6)
I believe the answer is:
ordinary seaman
'he'll be promoted if he's able and vice versa' is the definition.
The definition suggests a singular noun which matches the answer.
'he'll be promoted if he's' is the wordplay.
I cannot quite see how this works, but
'be' could be 'am' and 'am' is present in the answer.
'he' could be 'sean' and 'sean' is found within the remaining letters.
The remaining letters 'ordinary' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for ordinary seaman that I've seen before include "OS in full" , "Crew member" , "Lowest rank of Royal Navy sailor" .)