Inmate teased with a possible release (9)
I believe the answer is:
emanation
'release' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Maybe there's an association between them I don't understand?
'inmate teased with a possible' is the wordplay.
'teased with' indicates an anagram.
'possible' becomes 'on' ('not on' can mean unacceptable or not possible).
'inmate' anagrammed with 'a' can make 'emanati'.
'emanati'+'on'='EMANATION'
Can you help me to learn more?
(Other definitions for emanation that I've seen before include "Pouring out" , "discharge" , "Issue" , "produce radioactive gas" , "Something flowing out from a source" .)