Backing workers, Her Majesty gets into plates in chests (6)
I believe the answer is:
sterna
'plates in chests' is the definition.
The answer and definition can be both body parts as well as being plural nouns.
Perhaps there's a link between them I don't understand?
'backing workers her majesty gets into' is the wordplay.
'backing' says the letters should be written backwards.
'workers' becomes 'ants' (worker ants).
'her majesty' becomes 'ER' (Elizabeth Regina).
'gets into' means one lot of letters goes inside another.
'ants' written backwards gives 'stna'.
'stna' placed around 'er' is 'STERNA'.
Can you help me to learn more?
(Other definitions for sterna that I've seen before include "Bones in front" , "Formal backbones, Latin plural" , "Breastbones" .)