It's turned on behind grasping youth's back (5)
I believe the answer is:
lathe
'it's turned' is the definition.
I can't judge whether this definition defines the answer.
'behind grasping youth's back' is the wordplay.
'behind' becomes 'late' (as in behind schedule).
'grasping' means one lot of letters goes inside another (inserted letters are held or grasped).
'back' says to take the final letters (the letter at the back).
The final letter of 'youth' is 'h'.
'late' placed around 'h' is 'LATHE'.
'on' acts as a link.
Can you help me to learn more?
(Other definitions for lathe that I've seen before include "Turning instrument" , "Machine tool for shaping metal or wood" , "Wood-turning machine" , "Rotating machine tool" , "Machine for turning and shaping wood etc" .)