Appropriate piece of neckwear (6)
I believe the answer is:
collar
This clue could be a double definition.
'appropriate piece' is the first definition.
'collar' can be an answer for 'appropriate' (thesaurus). I'm not certain of the 'piece' bit.
'neckwear' is the second definition.
(thesaurus)
'of' acts as a link.
Can you help me to learn more?
(Other definitions for collar that I've seen before include "Apprehend (colloq.); cut of bacon" , "Item worn around the neck" , "Be hot under the . . . . . . to be angry or resentful" , "Appropriate - piece of neckwear" , "Ruff" .)