Group of three part-patriots (4)
I believe the answer is:
trio
'group of three' is the definition.
(eg group of three musicians)
'part-patriots' is the wordplay.
'part' indicates the answer is hidden within the clue.
'TRIO' is hidden in the letters of 'patriots'.
(Other definitions for trio that I've seen before include "Riot (anag)" , "father, spirit and son" , "Musical group" , "Beethoven's 'Archduke', for example" , "Chamber group" .)