Trunk and spreading roots (5)
I believe the answer is:
torso
'trunk' is the definition.
('torso' can be a synonym of 'trunk')
'spreading roots' is the wordplay.
'spreading' is an anagram indicator.
'roots' is an anagram of 'TORSO'.
'and' acts as a link.
(Other definitions for torso that I've seen before include "Trunk of human body" , "Main part of human body" , "Piece of bronze" , "Chest" , "Roost (anag)" .)