Some ukulele men taking part (7)
I believe the answer is:
element
'part' is the definition.
(element is a kind of part)
'some ukulele men taking' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'ELEMENT' can be found hidden inside 'ukulele men taking'.
(Other definitions for element that I've seen before include "Ideal situation for someone" , "Wire in electric fire" , "Chemical building-block" , "part of cooker" , "piece" .)