Habitual criminal given oxygen on water in atoll (6)
I believe the answer is:
lagoon
'water in atoll' is the definition.
'lagoon' can be an answer for 'atoll' (I've seen this in another clue). I am not sure about the 'water in' bit.
'habitual criminal given oxygen on' is the wordplay.
'habitual criminal' becomes 'lag' (slang term for a prisoner. I am not sure about the 'habitual' bit.).
'given' is a charade indicator (letters next to each other).
'oxygen' becomes 'O' (O is the chemical symbol for oxygen).
'lag'+'o'+'on'='LAGOON'
Can you help me to learn more?
(Other definitions for lagoon that I've seen before include "A slat-water lake" , "Calm water behind reef" , "Salt-water lake, often blue" , "Shallow salt-water lake" , "Body of salt water cut off from the sea" .)