Unusual action did result from this dependency (9)
I believe the answer is:
addiction
'from this dependency' is the definition.
'addiction' can be an answer for 'dependency' (synonyms). I'm unsure of the rest of the definition.
'unusual action did' is the wordplay.
'unusual' indicates anagramming the letters.
'action'+'did'='actiondid'
'actiondid' anagrammed gives 'ADDICTION'.
'result' acts as a link.
Can you help me to learn more?
(Other definitions for addiction that I've seen before include "Bug one's caught" , "hard to stop" , "Obsession" , "I did act on (anag.)" , "habit that's hard to break" .)