Gutsy star, thick-skinned, is a piece of work (4)
I believe the answer is:
task
'piece of work' is the definition.
(I've seen this before)
'gutsy star thick-skinned is a' is the wordplay.
I cannot really understand how this works, but
'a' is present in the answer.
The remaining letters 'tsk' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for task that I've seen before include "Set piece of work" , "Assignment" , "Burden with work" , "something to do" , "Job, undertaking" .)