Tender for sudible tool (4)
I believe the answer is:
sore
'tender' is the definition.
(synonyms)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for sore that I've seen before include "Causing or suffering pain" , "Eros (anag.)" , "Tender spot" , "Painfully sensitive" , "Rose (anag.)" .)