Composer about to jump aboard (6)
I believe the answer is:
chopin
'composer' is the definition.
(Frederic Chopin)
'about to jump aboard' is the wordplay.
I cannot quite understand how this works, but
'about' could be 'c' (abbreviation for circa) and 'c' is present in the answer.
'jump' could be 'hop' (hop is a kind of jump) and 'hop' is present in the answer.
'aboard' could be 'in' (eg in a vehicle) and 'in' is present in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for chopin that I've seen before include "his writing noted" , "See 10" , "Double centenarian" , "popular composer" , "Polish composer of much piano music" .)