A university man breaking into a mechanised system (10)
I believe the answer is:
automation
'a mechanised system' is the definition.
(doing things with machines)
'a university man breaking into' is the wordplay.
'university' becomes 'u' (abbreviation for university).
'man' becomes 'toma' (I can't explain this - if you can you should believe this answer much more).
'breaking' indicates anagramming the letters.
'into' is an anagram of 'tion'.
'a'+'u'+'toma'+'tion'='AUTOMATION'
(Other definitions for automation that I've seen before include "Highly mechanised processing" , "Process" , "labour-saving system" .)