Worker and boss protecting king and queen -- one receives a blow (12)
I believe the answer is:
handkerchief
'one receives a blow' is the definition.
(you blow your nose into a handkerchief)
'worker and boss protecting king and queen' is the wordplay.
I cannot really understand how this works, but
'worker' could be 'hand' (hand is a kind of worker) and 'hand' is found within the answer.
'boss' could be 'chief' (synonyms) and 'chief' is found in the answer.
'king' could be 'er' (abbreviation for Edward Rex, various English kings) and 'er' is found in the answer.
A single letter 'k' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for handkerchief that I've seen before include "piece of cloth" , "Cloth for wiping nose" , "Suit pocket accessory" , "Sneeze catcher" , "Nose rag" .)