Fasten piece of wood (5)
I believe the answer is:
stick
This clue is a triple definition!
'fasten' is the first definition.
(I know that stick is a kind of fasten)
'piece' is the second definition.
(stick is a kind of piece)
'of' acts as a link.
'wood' is the third definition.
(thesaurus)
(Other definitions for stick that I've seen before include "Endure" , "Baton; gum" , "Tolerate" , "Gear lever; adhere" , "Adhere; baton" .)