Twins in heritage ministry (6)
I believe the answer is:
gemini
'twins' is the definition.
(twins are the symbol of the star sign Gemini)
'in heritage ministry' is the wordplay.
'in' says the answer is hidden in the clue.
'GEMINI' is hidden within 'heritage ministry'.
(Other definitions for gemini that I've seen before include "star group" , "lot of stars" , "Zodiacal twins" , "Heavenly sign of the Twins" , "May person" .)