Christmas entertainment on tap, perhaps (5)
I believe the answer is:
panto
'christmas entertainment' is the definition.
(I've seen this before)
'on tap perhaps' is the wordplay.
'perhaps' is an anagram indicator.
'on'+'tap'='ontap'
'ontap' anagrammed gives 'PANTO'.
(Other definitions for panto that I've seen before include "Dick Whittington" , "In brief, traditional Christmas entertainment" , "Traditional seasonal entertainment (abbr)" , "theatrical work" , "Christmas entertainment (abbr.)" .)