Is old feeling of delight not starting, being alone? (9)
I believe the answer is:
isolation
'being alone?' is the definition.
(being isolated or on one's own)
'is old feeling of delight not starting' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'feeling of delight' becomes 'elation'.
'not starting' means to remove the first letter.
'elation' with its initial letter taken off is 'lation'.
'is'+'o'+'lation'='ISOLATION'
(Other definitions for isolation that I've seen before include "Staff in such a hospital working with" , "Remoteness" , "Remote and lonely state" , "State of separation, closing off" , "loneliness" .)