One on rink maybe, sister, hugging Catherine (6)
I believe the answer is:
skater
'one on rink' is the definition.
(an ice skater on an ice rink)
'sister hugging catherine' is the wordplay.
'sister' becomes 'sr' (abbreviation as in names of nuns).
'hugging' is an insertion indicator.
'catherine' becomes 'Kate'.
'sr' enclosing 'kate' is 'SKATER'.
'maybe' acts as a link.
(Other definitions for skater that I've seen before include "Ice sportsman" , "Athlete on blades" , "One glides on wheels or blades" , "Winter sportsperson" , "Mover across ice" .)