Take on US prison where child may be behind bars (7)
I believe the answer is:
playpen
'where child may be behind bars' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.
'take on us prison' is the wordplay.
'take on' becomes 'play' (synonyms).
'us prison' becomes 'pen' (short for penitentiary).
'play'+'pen'='PLAYPEN'
Can you help me to learn more?
(Other definitions for playpen that I've seen before include "Portable enclosure for young-child" , "Limited room for amusement" , "Toddler's enclosure" , "Enclosure for kids" , "Portable enclosure for tots" .)