Wood used in tribal sacrifice (5)
I believe the answer is:
balsa
'wood' is the definition.
(type of wood)
'in tribal sacrifice' is the wordplay.
'in' indicates the answer is hidden within the clue.
'BALSA' is hidden within 'tribal sacrifice'.
'used' acts as a link.
(Other definitions for balsa that I've seen before include "Wood used in model making" , "Tropical American tree" , "Central American forest tree used to make floats, rafts, models etc" , "Tree yielding light wood" , "Tree with light soft wood" .)