Seasonal entertainment on tap, perhaps (5)
I believe the answer is:
panto
'seasonal entertainment' is the definition.
(pantomime)
'on tap perhaps' is the wordplay.
'perhaps' indicates anagramming the letters.
'on'+'tap'='ontap'
'ontap' anagrammed gives 'PANTO'.
(Other definitions for panto that I've seen before include "Slapstick theatre for children (abbr)" , "Christmas show" , "In brief, traditional Christmas entertainment" , "cross-dressing performance" , "Christmas entertainment (abbr.)" .)