Dwarf tree (6)
I believe the answer is:
bonsai
'dwarf tree' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for bonsai that I've seen before include "Tree-dwarfing art" , "Tiny Japanese tree" , "small growth" , "Japanese art of growing dwarf trees" , "Very little tree" .)