Pro-PC idiot's not half arsy - protection needed for chair (12)
I believe the answer is:
antimacassar
'for chair' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'pro-pc idiot's not half arsy protection' is the wordplay.
I cannot really understand how this works, but
'pc' could be 'mac' (I've seen this before) and 'mac' is present in the answer.
'not' could be 'nt' (synonyms) and 'nt' is located in the answer.
'idiot' could be 'ass' (I've seen this in other clues) and 'ass' is present in the answer.
This explanation may well be incorrect...
'needed' acts as a link.
Can you help me to learn more?
(Other definitions for antimacassar that I've seen before include "Chair back protector" , "Cloth protecting chair from grease" , "It keeps hair oil off the back of a chair" , "Protective cloth on upholstered seat" , "Protective chair cover" .)