Reportedly line dancing in white (3,4)
I believe the answer is:
cue ball
'white' is the definition.
(the cue ball in snooker is also called the white)
'reportedly line dancing' is the wordplay.
'reportedly' shows a homophone (sound like).
'line' becomes 'queue' (queue is a kind of line).
'dancing' becomes 'ball'.
'queue' sounds like 'cue'.
'cue'+'ball'='CUE-BALL'
'in' acts as a link.
(Other definitions for cue ball that I've seen before include "Object struck by a snooker player" , "Feature of pub entertainment" , "Jimmy White's white?" , "The white in snooker" .)