Split piece of garlic (5)
I believe the answer is:
clove
I believe this clue is a double definition.
'split' is the first definition.
(I've seen this before)
'piece of garlic' is the second definition.
(I've seen this in another clue)
(Other definitions for clove that I've seen before include "Spice, used whole or ground" , "A spice; a garlic bulb" , "Aromatic bud" , "Flower bud used as a spice" , "Pungent spice" .)