A tool used to cut thatch is elongated to some extent (6)
I believe the answer is:
chisel
'a tool' is the definition.
(chisel is a kind of tool)
'thatch is elongated to some extent' is the wordplay.
'to some extent' indicates the answer is hidden within the clue.
'CHISEL' is hidden in the letters of 'thatch is elongated'.
'used to cut' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for chisel that I've seen before include "Sculpting tool" , "Tool for shaping wood or metal" , "Sculptor's tool" , "Hammered cutting tool" , "Wood-shaping tool" .)