Sit around; Rip returns with enthusiasm (6)
I believe the answer is:
spirit
'enthusiasm' is the definition.
(I've seen this before)
'sit around rip returns' is the wordplay.
'around' is an insertion indicator.
'returns' says the letters should be written backwards.
'rip' reversed gives 'pir'.
'sit' enclosing 'pir' is 'SPIRIT'.
'with' is the link.
(Other definitions for spirit that I've seen before include "Distilled alcoholic drink" , "eg Whisky or gin" , "Wraith" , "Courage, strong drink" , "enthusiasm" .)