Deplorable, but very good around half term (7)
I believe the answer is:
piteous
'deplorable' is the definition.
(thesaurus)
'very good around half term' is the wordplay.
'very good' becomes 'pious' (pious can mean very religious).
'around' means one lot of letters goes inside another.
'half' means to take half the letters.
'term' halved is 'te'.
'pious' placed around 'te' is 'PITEOUS'.
'but' is the link.
(Other definitions for piteous that I've seen before include "Deserving sympathy" , "Woeful" , "Deserving compassion" , "Arousing sorrow and compassion" , "Heart-rending" .)