Puzzle noticed after dance (6)
I believe the answer is:
jigsaw
'puzzle' is the definition.
(jigsaw puzzle is a type of puzzle)
'noticed after dance' is the wordplay.
'noticed' becomes 'saw' (I've seen this in another clue).
'after' means one lot of letters go next to another.
'dance' becomes 'jig' (jig is a kind of dance).
'saw' put after 'jig' is 'JIGSAW'.
(Other definitions for jigsaw that I've seen before include "Sharp tool (for cutting puzzle into pieces?)" , "Kind of puzzle" , "Problem with fitting in" , "As pastime" , "Puzzle-maker" .)