Worry about a guitar piece? (4)
I believe the answer is:
fret
'worry' is the definition.
(to fret about something is to worry)
'about a guitar piece?' is the wordplay.
'about' is an insertion indicator.
'a guitar' becomes 'fet' (I can't explain this - if you can you should believe this answer much more).
'piece?' becomes 'r' (abbreviation for Rook).
'fet' placed around 'r' is 'FRET'.
Can you help me to learn more?
(Other definitions for fret that I've seen before include "Chafe; worry" , "Notes separator" , "Worry unnecessarily" , "Worry; wet mist" , "Vex oneself - part of a fingerboard" .)