Colourful bit of square dancing (3)
I believe the answer is:
red
'colourful' is the definition.
('red' can be similar in meaning to 'colourful')
'bit of square dancing' is the wordplay.
'bit of' indicates the answer is hidden within the clue.
'RED' can be found hidden inside 'square dancing'.
(Other definitions for red that I've seen before include "socialist?" , "Colour for a blusher" , "could be a Marxist" , "- Cross; - admiral" , "Scarlet or vermilion" .)