Steps of area within prison (5)
I believe the answer is:
stair
'steps' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'area within prison' is the wordplay.
'area' becomes 'a' (maths abbreviation).
'within' is an insertion indicator.
'prison' becomes 'stir' (informal term for prison).
'a' placed into 'stir' is 'STAIR'.
'of' is the link.
Can you help me to learn more?
(Other definitions for stair that I've seen before include "Bit of a flight!" , "this could get one down" , "Rising step" , "one on the way up" , "means to go down" .)