Christmas visitors can include one conjuror (8)
I believe the answer is:
magician
'conjuror' is the definition.
(synonyms)
'christmas visitors can include one' is the wordplay.
'christmas visitors' becomes 'magi' (the wise men of the nativity).
'include' is an insertion indicator.
'one' becomes 'i' (Roman numeral).
'can' going around 'i' is 'cian'.
'magi'+'cian'='MAGICIAN'
(Other definitions for magician that I've seen before include "Wizard like cartoon Mandrake" , "trickster" , "Sorcerer, wizard" , "Stage conjurer or maker of legerdemain" , "Conjuror, wizard" .)