Guide plays her party piece (6)
I believe the answer is:
sherpa
'guide' is the definition.
(Himalayan mountain guide)
'plays her party piece' is the wordplay.
'piece' indicates a hidden word.
'SHERPA' can be found hidden inside 'plays her party'.
(Other definitions for sherpa that I've seen before include "Asian language" , "one to climb mountains maybe" , "porter" , "Nepal-Tibet native" , "Native Himalayan mountain climber" .)