Professional originally glad about ship's advance (8)
I believe the answer is:
progress
'advance' is the definition.
(to progress is to advance)
'professional originally glad about ship's' is the wordplay.
'professional' becomes 'pro' (abbreviation).
'originally' indicates taking the first letters.
'about' becomes 're' ('re' means regarding or about).
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
The initial letter of 'glad' is 'g'.
'pro'+'g'+'re'+'ss'='PROGRESS'
(Other definitions for progress that I've seen before include "Relating to verse" , "Headway" , "Mature" , "Advance - promotion" , "Forward movement towards a destination or goal" .)