Extra cheap displays of breathing space (7)
I believe the answer is:
trachea
'breathing space' is the definition.
The answer and definition can be both body parts as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'extra cheap displays' is the wordplay.
'displays' indicates the answer is hidden within the clue.
'TRACHEA' is hidden in the letters of 'extra cheap'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for trachea that I've seen before include "where air passes" , "Breathing tube" , "Tube taking inhaled air from the larynx" , "pipe" , "It connects the larynx and bronchi" .)